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Full vulnerability report · 2024
CVE-2021-47557High confidence

net/sched: sch_ets: don't peek at classes beyond 'nbands'

Linux · Linux

5.5MediumCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 16 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Low, lowered one band.downgradedsince 11 May 2026

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.24% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Linux Linux and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 16 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.15.15-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.15.15-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.15.15-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.5.15.15-1Debian Security Tracker ↗Source updated 5 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2021-47557 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitykernel: net/sched: sch_ets: don't peek at classes beyond 'nbands'
16 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • kernel-rt as a component of Red Hat Enterprise Linux 8
  • kernel-rt-core as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-core as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-devel as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-kvm as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-modules as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-modules-extra as a component of Red Hat Enterprise Linux 8
  • kernel-rt-debug-modules-internal as a component of Red Hat Enterprise Linux 8
  • kernel-rt-devel as a component of Red Hat Enterprise Linux 8
  • kernel-rt-kvm as a component of Red Hat Enterprise Linux 8
  • kernel-rt-modules as a component of Red Hat Enterprise Linux 8
Summary
A vulnerability was found in the Linux kernel's net/sched implementation, in the ETS module, where the system attempts to access classes beyond the defined limits, leading to a potential NULL pointer dereference. As a result, this can cause system crashes, disrupt network traffic.
Remediation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-34559

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 16 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't peek at classes beyond 'nbands' when the number of DRR classes decreases, the round-robin active list can contain elements that have already been freed in ets_qdisc_change(). As a consequence, it's possible to see a NULL dereference crash, caused by the attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets] Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100 FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0 Call Trace: <TASK> qdisc_peek_dequeued+0x29/0x70 [sch_ets] tbf_dequeue+0x22/0x260 [sch_tbf] __qdisc_run+0x7f/0x630 net_tx_action+0x290/0x4c0 __do_softirq+0xee/0x4f8 irq_exit_rcu+0xf4/0x130 sysvec_apic_timer_interrupt+0x52/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0033:0x7f2aa7fc9ad4 Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460 </TASK> Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000018 Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to remove from the active list those elements that are no more SP nor DRR. [1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/ v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock acquired, thanks to Cong Wang. v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb from the next list item.

What

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't peek at classes beyond 'nbands' when the number of DRR classes decreases, the round-robin active list can contain elements that have already been freed in ets_qdisc_change(). As a consequence, it's possible to see a NULL dereference crash, caused by the attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets] Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100 FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0 Call Trace: <TASK> qdisc_peek_dequeued+0x29/0x70 [sch_ets] tbf_dequeue+0x22/0x260 [sch_tbf] __qdisc_run+0x7f/0x630 net_tx_action+0x290/0x4c0 __do_softirq+0xee/0x4f8 irq_exit_rcu+0xf4/0x130 sysvec_apic_timer_interrupt+0x52/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0033:0x7f2aa7fc9ad4 Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460 </TASK> Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000018 Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to remove from the active list those elements that are no more SP nor DRR. [1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/ v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock acquired, thanks to Cong Wang. v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb from the next list item.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_ets: don't peek at classes beyond 'nbands' when the number of DRR classes decreases, the round-robin active list can contain elements that have already been freed in ets_qdisc_change(). As a consequence, it's possible to see a NULL dereference crash, caused by the attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014 RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets] Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287 RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000 RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0 R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100 FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0 Call Trace: <TASK> qdisc_peek_dequeued+0x29/0x70 [sch_ets] tbf_dequeue+0x22/0x260 [sch_tbf] __qdisc_run+0x7f/0x630 net_tx_action+0x290/0x4c0 __do_softirq+0xee/0x4f8 irq_exit_rcu+0xf4/0x130 sysvec_apic_timer_interrupt+0x52/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0033:0x7f2aa7fc9ad4 Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00 RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202 RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720 RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720 RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460 </TASK> Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000018 Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to remove from the active list those elements that are no more SP nor DRR. [1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/ v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock acquired, thanks to Cong Wang. v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb from the next list item.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → NULL Pointer Dereference → disrupt the affected service
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-476 ↗

CWE-476: NULL Pointer Dereference. The product dereferences a pointer that it expects to be valid but is NULL.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
Denial of serviceCWE-476
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2024-1235Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service und unspezifische Angriffe

Ein lokaler Angreifer kann mehrere Schwachstellen im Linux-Kernel ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen oder unspezifische Angriffe durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20240529Security Bulletin 29 May 2024

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 29 May 2024, published on 29 May 2024. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0081Multiples vulnérabilités dans le noyau Linux de SUSE

nvier 2026 https://www.suse.com/support/update/announcement/2026/suse-su-20260209-1 Bulletin de sécurité SUSE SUSE-SU-2026:0216-1 du 22 janvier 2026 https://www.suse.com/support/update/announcement/2026/suse-su-20260216-1 Bulletin de sécurité SUSE SUSE-SU-2026:0246-1 du 22 janvier 2026 https://www.suse.com/support/update/announcement/2026/suse-su-20260246-1 Bulletin de sécurité SUSE SUSE-SU-2026:0247-1 du 22 janvier 2026 https://www.suse.com/support/update/announcement/2026/suse-su-20260247-1 Bulletin de sécurité SUSE SUSE-SU-2026:0262-1 du 22 janvier 2026 https://www.suse.com/support/update/announcement/2026/suse-su-20260262-1 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47595 https://www.cve.org/CVERecord?id=CVE-2021-47595 Référence CVE CVE-2022-1679 https://www.cve.org/CVERecord?id=CVE-2022-1679 Référence CVE CVE-2022-2585 https://www.cve.org/CVERecord?id=CVE-2022-2585 Référence CVE CVE-2022-2586 https://www.cve.org/CVERecord?id=CVE-2022-2586 Référence CVE CVE-2022-2905 https://www.cve.org/CVERecord?id=CVE-2022-2905 Référence CVE CVE-2022-3564 https://www.cve.org/CVERecord?id=CVE-2022-3564 Référence CVE CVE-2022-3619 https://www.cve.org/CVERecord?id=CVE-2022-3619 Référence CVE CVE-2022-3640 https://www.cve.org/CVERecord?id=CVE-2022-3640

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-1009Multiples vulnérabilités dans le noyau Linux de SUSE

e 2025 https://www.suse.com/support/update/announcement/2025/suse-su-20254059-1 Bulletin de sécurité SUSE SUSE-SU-2025:4062-1 du 11 novembre 2025 https://www.suse.com/support/update/announcement/2025/suse-su-20254062-1 Bulletin de sécurité SUSE SUSE-SU-2025:4063-1 du 12 novembre 2025 https://www.suse.com/support/update/announcement/2025/suse-su-20254063-1 Bulletin de sécurité SUSE SUSE-SU-2025:4064-1 du 12 novembre 2025 https://www.suse.com/support/update/announcement/2025/suse-su-20254064-1 Bulletin de sécurité SUSE SUSE-SU-2025:4078-1 du 12 novembre 2025 https://www.suse.com/support/update/announcement/2025/suse-su-20254078-1 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47595 https://www.cve.org/CVERecord?id=CVE-2021-47595 Référence CVE CVE-2022-1679 https://www.cve.org/CVERecord?id=CVE-2022-1679 Référence CVE CVE-2022-2585 https://www.cve.org/CVERecord?id=CVE-2022-2585 Référence CVE CVE-2022-2586 https://www.cve.org/CVERecord?id=CVE-2022-2586 Référence CVE CVE-2022-2905 https://www.cve.org/CVERecord?id=CVE-2022-2905 Référence CVE CVE-2022-3564 https://www.cve.org/CVERecord?id=CVE-2022-3564 Référence CVE CVE-2022-3619 https://www.cve.org/CVERecord?id=CVE-2022-3619 Référence CVE CVE-2022-3640 https://www.cve.org/CVERecord?id=CVE-2022-3640

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-0649Multiples vulnérabilités dans le noyau Linux de SUSE

Branch Server 4.3 SUSE Manager Server 4.3 Résumé De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur. Solutions Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation). Documentation Bulletin de sécurité SUSE SUSE-SU-2025:02537-1 du 28 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502537-1 Bulletin de sécurité SUSE SUSE-SU-2025:02538-1 du 28 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502538-1 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47595 https://www.cve.org/CVERecord?id=CVE-2021-47595 Référence CVE CVE-2022-1679 https://www.cve.org/CVERecord?id=CVE-2022-1679 Référence CVE CVE-2022-2585 https://www.cve.org/CVERecord?id=CVE-2022-2585 Référence CVE CVE-2022-2586 https://www.cve.org/CVERecord?id=CVE-2022-2586 Référence CVE CVE-2022-2905 https://www.cve.org/CVERecord?id=CVE-2022-2905 Référence CVE CVE-2022-3903 https://www.cve.org/CVERecord?id=CVE-2022-3903 Référence CVE CVE-2022-4095 https://www.cve.org/CVERecord?id=CVE-2022-4095 Référence CVE CVE-2022-4662 https://www.cve.org/CVERecord?id=CVE-2022-4662

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-0607Multiples vulnérabilités dans le noyau Linux de SUSE

urité SUSE SUSE-SU-2025:02333-1 du 16 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502333-1 Bulletin de sécurité SUSE SUSE-SU-2025:02334-1 du 16 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502334-1 Bulletin de sécurité SUSE SUSE-SU-2025:02335-1 du 16 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502335-1 Référence CVE CVE-2021-47212 https://www.cve.org/CVERecord?id=CVE-2021-47212 Référence CVE CVE-2021-47455 https://www.cve.org/CVERecord?id=CVE-2021-47455 Référence CVE CVE-2021-47527 https://www.cve.org/CVERecord?id=CVE-2021-47527 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47595 https://www.cve.org/CVERecord?id=CVE-2021-47595 Référence CVE CVE-2022-1679 https://www.cve.org/CVERecord?id=CVE-2022-1679 Référence CVE CVE-2022-21546 https://www.cve.org/CVERecord?id=CVE-2022-21546 Référence CVE CVE-2022-2585 https://www.cve.org/CVERecord?id=CVE-2022-2585 Référence CVE CVE-2022-2586 https://www.cve.org/CVERecord?id=CVE-2022-2586 Référence CVE CVE-2022-2905 https://www.cve.org/CVERecord?id=CVE-2022-2905 Référence CVE CVE-2022-3903 https://www.cve.org/CVERecord?id=CVE-2022-3903 Référence CVE CVE-2022-4095 https://www.cve.org/CVERecord?id=CVE-2022-40

Official advisory ↗
CERT-FR · French · CERTFR-2025-AVI-0587Multiples vulnérabilités dans le noyau Linux de SUSE

pour l'obtention des correctifs (cf. section Documentation). Documentation Bulletin de sécurité SUSE SUSE-SU-2025:02249-1 du 08 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502249-1 Bulletin de sécurité SUSE SUSE-SU-2025:02254-1 du 08 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502254-1 Bulletin de sécurité SUSE SUSE-SU-2025:02262-1 du 09 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502262-1 Bulletin de sécurité SUSE SUSE-SU-2025:02264-1 du 10 juillet 2025 https://www.suse.com/support/update/announcement/2025/suse-su-202502264-1 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47595 https://www.cve.org/CVERecord?id=CVE-2021-47595 Référence CVE CVE-2022-1679 https://www.cve.org/CVERecord?id=CVE-2022-1679 Référence CVE CVE-2022-2585 https://www.cve.org/CVERecord?id=CVE-2022-2585 Référence CVE CVE-2022-2586 https://www.cve.org/CVERecord?id=CVE-2022-2586 Référence CVE CVE-2022-2905 https://www.cve.org/CVERecord?id=CVE-2022-2905 Référence CVE CVE-2022-3564 https://www.cve.org/CVERecord?id=CVE-2022-3564 Référence CVE CVE-2022-3619 https://www.cve.org/CVERecord?id=CVE-2022-3619 Référence CVE CVE-2022-3640 https://www.cve.org/CVERecord?id=CVE-2022-3640

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0526Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2021-47548 Référence CVE CVE-2021-47549 https://www.cve.org/CVERecord?id=CVE-2021-47549 Référence CVE CVE-2021-47550 https://www.cve.org/CVERecord?id=CVE-2021-47550 Référence CVE CVE-2021-47551 https://www.cve.org/CVERecord?id=CVE-2021-47551 Référence CVE CVE-2021-47552 https://www.cve.org/CVERecord?id=CVE-2021-47552 Référence CVE CVE-2021-47553 https://www.cve.org/CVERecord?id=CVE-2021-47553 Référence CVE CVE-2021-47554 https://www.cve.org/CVERecord?id=CVE-2021-47554 Référence CVE CVE-2021-47555 https://www.cve.org/CVERecord?id=CVE-2021-47555 Référence CVE CVE-2021-47556 https://www.cve.org/CVERecord?id=CVE-2021-47556 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47558 https://www.cve.org/CVERecord?id=CVE-2021-47558 Référence CVE CVE-2021-47559 https://www.cve.org/CVERecord?id=CVE-2021-47559 Référence CVE CVE-2021-47560 https://www.cve.org/CVERecord?id=CVE-2021-47560 Référence CVE CVE-2021-47562 https://www.cve.org/CVERecord?id=CVE-2021-47562 Référence CVE CVE-2021-47563 https://www.cve.org/CVERecord?id=CVE-2021-47563 Référence CVE CVE-2021-47564 https://www.cve.org/CVERecord?id=CVE-2021-47564 Référence CVE CVE-2021-47565 https://www.cve.org/CVERecord?id=CVE-2021-47565 Référence CVE CVE-2021-47569 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0496Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2021-47548 Référence CVE CVE-2021-47549 https://www.cve.org/CVERecord?id=CVE-2021-47549 Référence CVE CVE-2021-47550 https://www.cve.org/CVERecord?id=CVE-2021-47550 Référence CVE CVE-2021-47551 https://www.cve.org/CVERecord?id=CVE-2021-47551 Référence CVE CVE-2021-47552 https://www.cve.org/CVERecord?id=CVE-2021-47552 Référence CVE CVE-2021-47553 https://www.cve.org/CVERecord?id=CVE-2021-47553 Référence CVE CVE-2021-47554 https://www.cve.org/CVERecord?id=CVE-2021-47554 Référence CVE CVE-2021-47555 https://www.cve.org/CVERecord?id=CVE-2021-47555 Référence CVE CVE-2021-47556 https://www.cve.org/CVERecord?id=CVE-2021-47556 Référence CVE CVE-2021-47557 https://www.cve.org/CVERecord?id=CVE-2021-47557 Référence CVE CVE-2021-47558 https://www.cve.org/CVERecord?id=CVE-2021-47558 Référence CVE CVE-2021-47559 https://www.cve.org/CVERecord?id=CVE-2021-47559 Référence CVE CVE-2021-47560 https://www.cve.org/CVERecord?id=CVE-2021-47560 Référence CVE CVE-2021-47562 https://www.cve.org/CVERecord?id=CVE-2021-47562 Référence CVE CVE-2021-47563 https://www.cve.org/CVERecord?id=CVE-2021-47563 Référence CVE CVE-2021-47564 https://www.cve.org/CVERecord?id=CVE-2021-47564 Référence CVE CVE-2021-47565 https://www.cve.org/CVERecord?id=CVE-2021-47565 Référence CVE CVE-2021-47569 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-021512Linux の Linux Kernel における NULL ポインタデリファレンスに関する脆弱性

Linux の Linux Kernel には、NULL ポインタデリファレンスに関する脆弱性が存在します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
Fixed
Linux: < 5.6, 5.10.83 ≤ 5.10.*, 5.15.6 ≤ 5.15.*, 5.16 ≤ *
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
04

Evidence and provenance

Published 24 May 2024 · Last source change 11 May 2026, 13:56 UTC · CWE-476 · NULL Pointer Dereference

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-34559
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceNIST NVD
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-34559↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference↗Patch or update reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-47557 · cve.blacktree.nl