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Full vulnerability report · 2025
CVE-2023-53599High confidence

crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390

Linux · Linux

7.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

9 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.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-6.11Affected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcp-6.11Affected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-hwe-6.11Affected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-intelAffected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatency-hwe-6.11Affected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-realtimeAffected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, 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 feedCanonical record ↗Source updated 9 Sept 2026
Optional official sources

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

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

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-2025-32263

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 actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390 Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point to the scatterlist array in areq->first_rsgl.sgl.sgl. Without this, the gcm-aes-s390 driver will oops when it tries to do gcm_walk_start() on req->dst because req->dst is set to the value of areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling aead_request_set_crypt(). The problem comes if an empty ciphertext is passed: the loop in af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl up. This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far as I can tell, that ignores req->dst and only uses req->src[*]. [*] Is this a bug in aesni-intel_glue.c? The s390x oops looks something like: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000a00000000 TEID: 0000000a00000803 Fault in home space mode while using kernel ASCE. AS:00000000a43a0007 R3:0000000000000024 Oops: 003b ilc:2 [#1] SMP ... Call Trace: [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390] [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8 [<00000000a2a60888>] aead_recvmsg+0x478/0x698 [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0 [<00000000a2e51a56>] sock_read_iter+0x76/0xa0 [<00000000a273e066>] vfs_read+0x26e/0x2a8 [<00000000a273e8c4>] ksys_read+0xbc/0x100 [<00000000a311d808>] __do_syscall+0x1d0/0x1f8 [<00000000a312ff30>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390]

What

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390 Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point to the scatterlist array in areq->first_rsgl.sgl.sgl. Without this, the gcm-aes-s390 driver will oops when it tries to do gcm_walk_start() on req->dst because req->dst is set to the value of areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling aead_request_set_crypt(). The problem comes if an empty ciphertext is passed: the loop in af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl up. This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far as I can tell, that ignores req->dst and only uses req->src[*]. [*] Is this a bug in aesni-intel_glue.c? The s390x oops looks something like: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000a00000000 TEID: 0000000a00000803 Fault in home space mode while using kernel ASCE. AS:00000000a43a0007 R3:0000000000000024 Oops: 003b ilc:2 [#1] SMP ... Call Trace: [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390] [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8 [<00000000a2a60888>] aead_recvmsg+0x478/0x698 [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0 [<00000000a2e51a56>] sock_read_iter+0x76/0xa0 [<00000000a273e066>] vfs_read+0x26e/0x2a8 [<00000000a273e8c4>] ksys_read+0xbc/0x100 [<00000000a311d808>] __do_syscall+0x1d0/0x1f8 [<00000000a312ff30>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390]

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 cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Fix missing initialisation affecting gcm-aes-s390 Fix af_alg_alloc_areq() to initialise areq->first_rsgl.sgl.sgt.sgl to point to the scatterlist array in areq->first_rsgl.sgl.sgl. Without this, the gcm-aes-s390 driver will oops when it tries to do gcm_walk_start() on req->dst because req->dst is set to the value of areq->first_rsgl.sgl.sgl by _aead_recvmsg() calling aead_request_set_crypt(). The problem comes if an empty ciphertext is passed: the loop in af_alg_get_rsgl() just passes straight out and doesn't set areq->first_rsgl up. This isn't a problem on x86_64 using gcmaes_crypt_by_sg() because, as far as I can tell, that ignores req->dst and only uses req->src[*]. [*] Is this a bug in aesni-intel_glue.c? The s390x oops looks something like: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000a00000000 TEID: 0000000a00000803 Fault in home space mode while using kernel ASCE. AS:00000000a43a0007 R3:0000000000000024 Oops: 003b ilc:2 [#1] SMP ... Call Trace: [<000003ff7fc3d47e>] gcm_walk_start+0x16/0x28 [aes_s390] [<00000000a2a342f2>] crypto_aead_decrypt+0x9a/0xb8 [<00000000a2a60888>] aead_recvmsg+0x478/0x698 [<00000000a2e519a0>] sock_recvmsg+0x70/0xb0 [<00000000a2e51a56>] sock_read_iter+0x76/0xa0 [<00000000a273e066>] vfs_read+0x26e/0x2a8 [<00000000a273e8c4>] ksys_read+0xbc/0x100 [<00000000a311d808>] __do_syscall+0x1d0/0x1f8 [<00000000a312ff30>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003ff7fc3e6b4>] gcm_aes_crypt+0x104/0xa68 [aes_s390]

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 cause the confidentiality, integrity or availability impact described by the vendor.

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 → cause the confidentiality, integrity or availability impact described by the vendor
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:H/I:H/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.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
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
CWE-476
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2025-2194Linux Kernel: Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen.

Official advisory
CERT-FR · French · CERTFR-2025-AVI-1073Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-53588 Référence CVE CVE-2023-53589 https://www.cve.org/CVERecord?id=CVE-2023-53589 Référence CVE CVE-2023-53591 https://www.cve.org/CVERecord?id=CVE-2023-53591 Référence CVE CVE-2023-53592 https://www.cve.org/CVERecord?id=CVE-2023-53592 Référence CVE CVE-2023-53593 https://www.cve.org/CVERecord?id=CVE-2023-53593 Référence CVE CVE-2023-53594 https://www.cve.org/CVERecord?id=CVE-2023-53594 Référence CVE CVE-2023-53596 https://www.cve.org/CVERecord?id=CVE-2023-53596 Référence CVE CVE-2023-53597 https://www.cve.org/CVERecord?id=CVE-2023-53597 Référence CVE CVE-2023-53598 https://www.cve.org/CVERecord?id=CVE-2023-53598 Référence CVE CVE-2023-53599 https://www.cve.org/CVERecord?id=CVE-2023-53599 Référence CVE CVE-2023-53600 https://www.cve.org/CVERecord?id=CVE-2023-53600 Référence CVE CVE-2023-53601 https://www.cve.org/CVERecord?id=CVE-2023-53601 Référence CVE CVE-2023-53602 https://www.cve.org/CVERecord?id=CVE-2023-53602 Référence CVE CVE-2023-53603 https://www.cve.org/CVERecord?id=CVE-2023-53603 Référence CVE CVE-2023-53604 https://www.cve.org/CVERecord?id=CVE-2023-53604 Référence CVE CVE-2023-53605 https://www.cve.org/CVERecord?id=CVE-2023-53605 Référence CVE CVE-2023-53607 https://www.cve.org/CVERecord?id=CVE-2023-53607 Référence CVE CVE-2023-53608 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2025-AVI-1047Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-53583 Référence CVE CVE-2023-53585 https://www.cve.org/CVERecord?id=CVE-2023-53585 Référence CVE CVE-2023-53587 https://www.cve.org/CVERecord?id=CVE-2023-53587 Référence CVE CVE-2023-53588 https://www.cve.org/CVERecord?id=CVE-2023-53588 Référence CVE CVE-2023-53589 https://www.cve.org/CVERecord?id=CVE-2023-53589 Référence CVE CVE-2023-53593 https://www.cve.org/CVERecord?id=CVE-2023-53593 Référence CVE CVE-2023-53594 https://www.cve.org/CVERecord?id=CVE-2023-53594 Référence CVE CVE-2023-53596 https://www.cve.org/CVERecord?id=CVE-2023-53596 Référence CVE CVE-2023-53597 https://www.cve.org/CVERecord?id=CVE-2023-53597 Référence CVE CVE-2023-53599 https://www.cve.org/CVERecord?id=CVE-2023-53599 Référence CVE CVE-2023-53600 https://www.cve.org/CVERecord?id=CVE-2023-53600 Référence CVE CVE-2023-53601 https://www.cve.org/CVERecord?id=CVE-2023-53601 Référence CVE CVE-2023-53602 https://www.cve.org/CVERecord?id=CVE-2023-53602 Référence CVE CVE-2023-53603 https://www.cve.org/CVERecord?id=CVE-2023-53603 Référence CVE CVE-2023-53604 https://www.cve.org/CVERecord?id=CVE-2023-53604 Référence CVE CVE-2023-53611 https://www.cve.org/CVERecord?id=CVE-2023-53611 Référence CVE CVE-2023-53613 https://www.cve.org/CVERecord?id=CVE-2023-53613 Référence CVE CVE-2023-53615 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2025-AVI-1032Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-53588 Référence CVE CVE-2023-53589 https://www.cve.org/CVERecord?id=CVE-2023-53589 Référence CVE CVE-2023-53591 https://www.cve.org/CVERecord?id=CVE-2023-53591 Référence CVE CVE-2023-53592 https://www.cve.org/CVERecord?id=CVE-2023-53592 Référence CVE CVE-2023-53593 https://www.cve.org/CVERecord?id=CVE-2023-53593 Référence CVE CVE-2023-53594 https://www.cve.org/CVERecord?id=CVE-2023-53594 Référence CVE CVE-2023-53596 https://www.cve.org/CVERecord?id=CVE-2023-53596 Référence CVE CVE-2023-53597 https://www.cve.org/CVERecord?id=CVE-2023-53597 Référence CVE CVE-2023-53598 https://www.cve.org/CVERecord?id=CVE-2023-53598 Référence CVE CVE-2023-53599 https://www.cve.org/CVERecord?id=CVE-2023-53599 Référence CVE CVE-2023-53600 https://www.cve.org/CVERecord?id=CVE-2023-53600 Référence CVE CVE-2023-53601 https://www.cve.org/CVERecord?id=CVE-2023-53601 Référence CVE CVE-2023-53602 https://www.cve.org/CVERecord?id=CVE-2023-53602 Référence CVE CVE-2023-53603 https://www.cve.org/CVERecord?id=CVE-2023-53603 Référence CVE CVE-2023-53604 https://www.cve.org/CVERecord?id=CVE-2023-53604 Référence CVE CVE-2023-53605 https://www.cve.org/CVERecord?id=CVE-2023-53605 Référence CVE CVE-2023-53607 https://www.cve.org/CVERecord?id=CVE-2023-53607 Référence CVE CVE-2023-53608 https://www.cve.org/CVERecord?id=

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

d?id=CVE-2023-53579 Référence CVE CVE-2023-53580 https://www.cve.org/CVERecord?id=CVE-2023-53580 Référence CVE CVE-2023-53581 https://www.cve.org/CVERecord?id=CVE-2023-53581 Référence CVE CVE-2023-53583 https://www.cve.org/CVERecord?id=CVE-2023-53583 Référence CVE CVE-2023-53585 https://www.cve.org/CVERecord?id=CVE-2023-53585 Référence CVE CVE-2023-53588 https://www.cve.org/CVERecord?id=CVE-2023-53588 Référence CVE CVE-2023-53593 https://www.cve.org/CVERecord?id=CVE-2023-53593 Référence CVE CVE-2023-53596 https://www.cve.org/CVERecord?id=CVE-2023-53596 Référence CVE CVE-2023-53597 https://www.cve.org/CVERecord?id=CVE-2023-53597 Référence CVE CVE-2023-53599 https://www.cve.org/CVERecord?id=CVE-2023-53599 Référence CVE CVE-2023-53600 https://www.cve.org/CVERecord?id=CVE-2023-53600 Référence CVE CVE-2023-53601 https://www.cve.org/CVERecord?id=CVE-2023-53601 Référence CVE CVE-2023-53602 https://www.cve.org/CVERecord?id=CVE-2023-53602 Référence CVE CVE-2023-53603 https://www.cve.org/CVERecord?id=CVE-2023-53603 Référence CVE CVE-2023-53611 https://www.cve.org/CVERecord?id=CVE-2023-53611 Référence CVE CVE-2023-53613 https://www.cve.org/CVERecord?id=CVE-2023-53613 Référence CVE CVE-2023-53615 https://www.cve.org/CVERecord?id=CVE-2023-53615 Référence CVE CVE-2023-53616 https://www.cve.org/CVERecord?id=

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.
Patch available
Affected
c1abe6f570aff4b6d396dc551e60570d2f50bd79 < 2c9d205040d7c0eaccc473917f9b0bb0a923e440; c1abe6f570aff4b6d396dc551e60570d2f50bd79 < 6a4b8aa0a916b39a39175584c07222434fa6c6ef; 6.5
Fixed
< 6.5; 6.5.3 ≤ 6.5.*; 6.6 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 4 Oct 2025 · Last source change 5 Aug 2026, 09:15 UTC · CWE-476 · NULL Pointer Dereference

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-2025-32263
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

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-2025-32263↗CVE authority or vendor 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-2023-53599 · cve.blacktree.nl