Full vulnerability report · 2026

CVE-2026-63993High confidence

vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()

Linux · Linux

9.8CriticalCVSS 3.1

Recommended action

Patch only the product branches with a verified fix

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 20 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product

Operational reassessment

Published severity in operational context

Open reassessment dashboard →

Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

No CISA KEV confirmation is currently recorded.
The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
EPSS is 0.51% for the current model date.

Compensating controls

Validate the affected product branch and deploy the verified fixed release.
Restrict the affected network interface to trusted sources where business-safe.
Monitor vendor guidance and exploitation sources for a material change.

Verification

Confirm that the asset runs Linux Linux and falls inside the recorded affected range.
Verify the installed build against the product-specific fixed version after deployment.
Validate exposure, authentication requirements and compensating controls in the actual environment.
Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 20 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Canonical Ubuntu Security: 20 affected package states with no published fix

Distribution package intelligence

Release-specific package status

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

24 package states

Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 20 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

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 release	Source package	Vendor state	Fixed version	Evidence
Debian trixietrixie · source	`linux`	Vendor fix publishedDebian records a fixed source-package version for this release.	`6.12.94-1`	Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · source	`linux`	Vendor fix publishedDebian records a fixed source-package version for this release.	`6.1.176-1`	Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · source	`linux`	Vendor fix publishedDebian records a fixed source-package version for this release.	`7.0.12-1`	Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · source	`linux`	Vendor fix publishedDebian records a fixed source-package version for this release.	`7.0.12-1`	Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-aws`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-azure`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-azure-fde`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-azure-nvidia`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-gcp`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-gke`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-gkeop`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-ibm`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-lowlatency`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-nvidia`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-nvidia-lowlatency`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-nvidia-tegra`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-oem-6.11`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-oracle`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-raspi`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-raspi-realtime`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-realtime`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-riscv`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archive	`linux-xilinx`	Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.	`Not published in this feed`	Canonical Ubuntu Security ↗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-2026-63993 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitykernel: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()

108 known affected

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

bpftool as a component of Red Hat Enterprise Linux 9
kernel as a component of Red Hat Enterprise Linux 9
kernel-64k as a component of Red Hat Enterprise Linux 9
kernel-64k-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-internal as a component of Red Hat Enterprise Linux 9

Summary: A flaw was found in the Linux kernel's Virtual Extensible LAN (VXLAN) module. This vulnerability occurs because a cached IP header pointer is improperly reused after a Path Maximum Transmission Unit (PMTU) check. When the packet's head is modified during the PMTU check, the old cached IP header pointer becomes invalid, leading to a Use-After-Free (UAF) condition. This memory corruption flaw can potentially allow an attacker to cause a system crash or execute arbitrary code.
Remediation: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture. Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available.

Recommended actionPatch only the product branches with a verified fix

Fix availability varies by product

What, why and how

In the Linux kernel, the following vulnerability has been resolved: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() skb_tunnel_check_pmtu() can change skb->head. Reusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF. Use instead ip_hdr(skb) as done in drivers/net/bareudp.c and drivers/net/geneve.c. Found by Sashiko.

What

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

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: a network path → Use After Free → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface: Network
Privileges required: None: unauthenticated exploitation is possible
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-416 ↗
CWE-416: Use After Free. The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
CVSS vector ? CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land: No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.

NetworkUnauthenticatedCWE-416

Official authority intelligence

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

ENISA EUVD · EUVD-2026-45566Official EUVD mapping

0 linked advisory records.

Official EUVD record ↗

BSI · German · WID-SEC-2026-2403Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, möglicherweise Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand herbeizuführen oder vertrauliche Informationen offenzulegen.

Official advisory ↗

Cyber Security Agency of Singapore · English · CSA-SB-20260722Security Bulletin 22 Jul 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 22 Jul 2026, published on 22 July 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1252Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-63984 Référence CVE CVE-2026-63985 https://www.cve.org/CVERecord?id=CVE-2026-63985 Référence CVE CVE-2026-63986 https://www.cve.org/CVERecord?id=CVE-2026-63986 Référence CVE CVE-2026-63987 https://www.cve.org/CVERecord?id=CVE-2026-63987 Référence CVE CVE-2026-63988 https://www.cve.org/CVERecord?id=CVE-2026-63988 Référence CVE CVE-2026-63989 https://www.cve.org/CVERecord?id=CVE-2026-63989 Référence CVE CVE-2026-63990 https://www.cve.org/CVERecord?id=CVE-2026-63990 Référence CVE CVE-2026-63991 https://www.cve.org/CVERecord?id=CVE-2026-63991 Référence CVE CVE-2026-63992 https://www.cve.org/CVERecord?id=CVE-2026-63992 Référence CVE CVE-2026-63993 https://www.cve.org/CVERecord?id=CVE-2026-63993 Référence CVE CVE-2026-63994 https://www.cve.org/CVERecord?id=CVE-2026-63994 Référence CVE CVE-2026-63995 https://www.cve.org/CVERecord?id=CVE-2026-63995 Référence CVE CVE-2026-63996 https://www.cve.org/CVERecord?id=CVE-2026-63996 Référence CVE CVE-2026-63997 https://www.cve.org/CVERecord?id=CVE-2026-63997 Référence CVE CVE-2026-63998 https://www.cve.org/CVERecord?id=CVE-2026-63998 Référence CVE CVE-2026-63999 https://www.cve.org/CVERecord?id=CVE-2026-63999 Référence CVE CVE-2026-64000 https://www.cve.org/CVERecord?id=CVE-2026-64000 Référence CVE CVE-2026-64001 https://www.cve.org/CVERecord?id=

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1255Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2026-63941 Référence CVE CVE-2026-63969 https://www.cve.org/CVERecord?id=CVE-2026-63969 Référence CVE CVE-2026-63970 https://www.cve.org/CVERecord?id=CVE-2026-63970 Référence CVE CVE-2026-63984 https://www.cve.org/CVERecord?id=CVE-2026-63984 Référence CVE CVE-2026-63985 https://www.cve.org/CVERecord?id=CVE-2026-63985 Référence CVE CVE-2026-63986 https://www.cve.org/CVERecord?id=CVE-2026-63986 Référence CVE CVE-2026-63987 https://www.cve.org/CVERecord?id=CVE-2026-63987 Référence CVE CVE-2026-63990 https://www.cve.org/CVERecord?id=CVE-2026-63990 Référence CVE CVE-2026-63992 https://www.cve.org/CVERecord?id=CVE-2026-63992 Référence CVE CVE-2026-63993 https://www.cve.org/CVERecord?id=CVE-2026-63993 Référence CVE CVE-2026-63995 https://www.cve.org/CVERecord?id=CVE-2026-63995 Référence CVE CVE-2026-63996 https://www.cve.org/CVERecord?id=CVE-2026-63996 Référence CVE CVE-2026-63997 https://www.cve.org/CVERecord?id=CVE-2026-63997 Référence CVE CVE-2026-63998 https://www.cve.org/CVERecord?id=CVE-2026-63998 Référence CVE CVE-2026-63999 https://www.cve.org/CVERecord?id=CVE-2026-63999 Référence CVE CVE-2026-64000 https://www.cve.org/CVERecord?id=CVE-2026-64000 Référence CVE CVE-2026-64001 https://www.cve.org/CVERecord?id=CVE-2026-64001 Référence CVE CVE-2026-64002 https://www.cve.org/CVERecord?id=

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1229Multiples vulnérabilités dans le noyau Linux d'Ubuntu

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1203Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-63952 Référence CVE CVE-2026-63974 https://www.cve.org/CVERecord?id=CVE-2026-63974 Référence CVE CVE-2026-63975 https://www.cve.org/CVERecord?id=CVE-2026-63975 Référence CVE CVE-2026-63976 https://www.cve.org/CVERecord?id=CVE-2026-63976 Référence CVE CVE-2026-63978 https://www.cve.org/CVERecord?id=CVE-2026-63978 Référence CVE CVE-2026-63979 https://www.cve.org/CVERecord?id=CVE-2026-63979 Référence CVE CVE-2026-63980 https://www.cve.org/CVERecord?id=CVE-2026-63980 Référence CVE CVE-2026-63984 https://www.cve.org/CVERecord?id=CVE-2026-63984 Référence CVE CVE-2026-63992 https://www.cve.org/CVERecord?id=CVE-2026-63992 Référence CVE CVE-2026-63993 https://www.cve.org/CVERecord?id=CVE-2026-63993 Référence CVE CVE-2026-63994 https://www.cve.org/CVERecord?id=CVE-2026-63994 Référence CVE CVE-2026-64000 https://www.cve.org/CVERecord?id=CVE-2026-64000 Référence CVE CVE-2026-64007 https://www.cve.org/CVERecord?id=CVE-2026-64007 Référence CVE CVE-2026-64010 https://www.cve.org/CVERecord?id=CVE-2026-64010 Référence CVE CVE-2026-64011 https://www.cve.org/CVERecord?id=CVE-2026-64011 Référence CVE CVE-2026-64015 https://www.cve.org/CVERecord?id=CVE-2026-64015 Référence CVE CVE-2026-64018 https://www.cve.org/CVERecord?id=CVE-2026-64018 Référence CVE CVE-2026-64025 https://www.cve.org/CVERecord?id=

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1162Multiples vulnérabilités dans le noyau Linux d'Ubuntu

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-1066Multiples vulnérabilités dans le noyau Linux d'Ubuntu

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-0954Multiples vulnérabilités dans le noyau Linux d'Ubuntu

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-0926Multiples vulnérabilités dans le noyau Linux d'Ubuntu

Official advisory ↗

JVN iPedia · Japanese · JVNDB-2026-036481LinuxのLinux Kernelにおける解放済みメモリの使用に関する脆弱性

Linuxカーネルにおいて、以下の脆弱性が修正されました。vxlan: skb_tunnel_check_pmtu()実行後にキャッシュされたip_hdr()の値を再利用しないでください。skb_tunnel_check_pmtu()はskb-＞headを変更する可能性があります。skb_tunnel_check_pmtu()の後でold_iphを再利用すると、Use-After-Free（UAF）が発生する可能性があります。代わりに、drivers/net/bareudp.cおよびdrivers/net/geneve.cで行われているようにip_hdr(skb)を使用してください。発見者はSashikoです。

Official advisory ↗

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: bpftool as a component of Red Hat Enterprise Linux 9
kernel as a component of Red Hat Enterprise Linux 9
kernel-64k as a component of Red Hat Enterprise Linux 9
kernel-64k-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-internal as a component of Red Hat Enterprise Linux 9
kernel-64k-debug-modules-partner as a component of Red Hat Enterprise Linux 9
kernel-64k-devel as a component of Red Hat Enterprise Linux 9
kernel-64k-devel-matched as a component of Red Hat Enterprise Linux 9
kernel-64k-modules as a component of Red Hat Enterprise Linux 9
kernel-64k-modules-core as a component of Red Hat Enterprise Linux 9
kernel-64k-modules-extra as a component of Red Hat Enterprise Linux 9
kernel-64k-modules-internal as a component of Red Hat Enterprise Linux 9
kernel-64k-modules-partner as a component of Red Hat Enterprise Linux 9
kernel-abi-stablelists as a component of Red Hat Enterprise Linux 9
kernel-core as a component of Red Hat Enterprise Linux 9
kernel-cross-headers as a component of Red Hat Enterprise Linux 9
kernel-debug as a component of Red Hat Enterprise Linux 9
kernel-debug-core as a component of Red Hat Enterprise Linux 9
kernel-debug-devel as a component of Red Hat Enterprise Linux 9
kernel-debug-devel-matched as a component of Red Hat Enterprise Linux 9
kernel-debug-modules as a component of Red Hat Enterprise Linux 9
kernel-debug-modules-core as a component of Red Hat Enterprise Linux 9
kernel-debug-modules-extra as a component of Red Hat Enterprise Linux 9
and 78 more
Fixed: kernel-64k-debug-debuginfo-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-64k-debug-devel-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-64k-debug-devel-matched-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-64k-debuginfo-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-64k-devel-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-64k-devel-matched-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-debuginfo-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-debuginfo-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-debuginfo-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-debuginfo-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-matched-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-matched-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-matched-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debug-devel-matched-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-common-aarch64-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-common-ppc64le-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-common-s390x-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-debuginfo-common-x86_64-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-devel-0:6.12.0-211.52.1.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-devel-0:6.12.0-211.52.1.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-devel-0:6.12.0-211.52.1.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
kernel-devel-0:6.12.0-211.52.1.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
and 279 more
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: No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.

Evidence and provenance

Published 19 Jul 2026 · Last source change 5 Aug 2026, 12:37 UTC · CWE-416 · Use After Free

CVE recordCVE.org · 5.2

CVSS sourceCNA

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-2026-45566

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 ↗

5 Aug 2026, 12:37 UTC
Vendor guidanceAuthoritative vendor guidance changed: added patch: git.kernel.org/5303925e360527243b46a440a04667826bbc72b7; added patch: git.kernel.org/609e63312c29aad18026a1d3222e123d4b6b0feb; 6 further additions.
Before
remediation: git.kernel.org/6b8bfce9d2f774d2c2243e0248e03efb99bba6c0
After
patch: git.kernel.org/5303925e360527243b46a440a04667826bbc72b7 · patch: git.kernel.org/609e63312c29aad18026a1d3222e123d4b6b0feb · patch: git.kernel.org/6b8bfce9d2f774d2c2243e0248e03efb99bba6c0 · 6 more references
git.kernel.org ↗
5 Aug 2026, 12:37 UTC
Affected versionsThe structured affected or fixed version information changed.
Before
4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 6b8bfce9d2f774d2c2243e0248e03efb99bba6c0; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 9257f56ac47ef1976bcd056cf986a9988eeec67a; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 8d435d68d71fb875876b722f4136caf74f2f48bd; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < dc3bfa050f873371e745bdf478b1f5b738e5733d; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 609e63312c29aad18026a1d3222e123d4b6b0feb; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 5303925e360527243b46a440a04667826bbc72b7; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < a493efd4336cf19122ae0e4cbb3d31b32d70deea; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 7d9ef0cb271555d8cf39fefe6c981e1493b25ecf · Fixed: < 5.9; 5.10.259 ≤ 5.10.*; 5.15.210 ≤ 5.15.*; 6.1.176 ≤ 6.1.*; 6.6.143 ≤ 6.6.*; 6.12.93 ≤ 6.12.*; 6.18.35 ≤ 6.18.*; 7.0.12 ≤ 7.0.*
After
Linux: 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 6b8bfce9d2f774d2c2243e0248e03efb99bba6c0, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 9257f56ac47ef1976bcd056cf986a9988eeec67a, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 8d435d68d71fb875876b722f4136caf74f2f48bd, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < dc3bfa050f873371e745bdf478b1f5b738e5733d, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 609e63312c29aad18026a1d3222e123d4b6b0feb, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 5303925e360527243b46a440a04667826bbc72b7, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < a493efd4336cf19122ae0e4cbb3d31b32d70deea, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 7d9ef0cb271555d8cf39fefe6c981e1493b25ecf, 5.9 · Fixed: Linux: < 5.9, 5.10.259 ≤ 5.10.*, 5.15.210 ≤ 5.15.*, 6.1.176 ≤ 6.1.*, 6.6.143 ≤ 6.6.*, 6.12.93 ≤ 6.12.*, 6.18.35 ≤ 6.18.*, 7.0.12 ≤ 7.0.*, 7.1 ≤ *
CNA ↗

2026-07-19CVE published

2026-08-05Fixed release or patch reference recorded

ENISA EUVD · EUVD-2026-45566↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference↗Patch or update 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.

vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()

Published severity in operational context

Evidence used

Compensating controls

Verification

Remediation availability differs by product scope

Release-specific package status

Authoritative vendor CSAF and VEX advisories

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

ENISA European Vulnerability Database

EUVD-2026-45566

What, why and how

Exploit reality and attack path

Official authority intelligence

Patch and workaround

Evidence and provenance

What changed after publication