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Full vulnerability report · 2025
CVE-2025-68299High confidence

afs: Fix delayed allocation of a cell's anonymous key

Linux · Linux

UnscoredAssess manually
Recommended action
Needs assessment

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.

Fix not verified
Distribution package intelligence

Ubuntu vendor package status

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

11 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-aws-6.17Affected, 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 10 Sept 2026
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 10 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 10 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 10 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 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-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 10 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 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracle-6.17Affected, 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 10 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 10 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 10 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 10 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-2025-203781

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 actionNeeds assessment

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.

Fix not verified
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous key is done in a background thread along with other cell setup such as doing a DNS upcall. In the reported bug, this is triggered by afs_parse_source() parsing the device name given to mount() and calling afs_lookup_cell() with the name of the cell. The normal key lookup then tries to use the key description on the anonymous authentication key as the reference for request_key() - but it may not yet be set and so an oops can happen. This has been made more likely to happen by the fix for dynamic lookup failure. Fix this by firstly allocating a reference name and attaching it to the afs_cell record when the record is created. It can share the memory allocation with the cell name (unfortunately it can't just overlap the cell name by prepending it with "afs@" as the cell name already has a '.' prepended for other purposes). This reference name is then passed to request_key(). Secondly, the anon key is now allocated on demand at the point a key is requested in afs_request_key() if it is not already allocated. A mutex is used to prevent multiple allocation for a cell. Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't yet allocated (if we need it) and then the caller can return -ECHILD to drop out of RCU-mode and afs_request_key() can be called. Note that the anonymous key is kind of necessary to make the key lookup cache work as that doesn't currently cache a negative lookup, but it's probably worth some investigation to see if NULL can be used instead.

What

In the Linux kernel, the following vulnerability has been resolved: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous key is done in a background thread along with other cell setup such as doing a DNS upcall. In the reported bug, this is triggered by afs_parse_source() parsing the device name given to mount() and calling afs_lookup_cell() with the name of the cell. The normal key lookup then tries to use the key description on the anonymous authentication key as the reference for request_key() - but it may not yet be set and so an oops can happen. This has been made more likely to happen by the fix for dynamic lookup failure. Fix this by firstly allocating a reference name and attaching it to the afs_cell record when the record is created. It can share the memory allocation with the cell name (unfortunately it can't just overlap the cell name by prepending it with "afs@" as the cell name already has a '.' prepended for other purposes). This reference name is then passed to request_key(). Secondly, the anon key is now allocated on demand at the point a key is requested in afs_request_key() if it is not already allocated. A mutex is used to prevent multiple allocation for a cell. Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't yet allocated (if we need it) and then the caller can return -ECHILD to drop out of RCU-mode and afs_request_key() can be called. Note that the anonymous key is kind of necessary to make the key lookup cache work as that doesn't currently cache a negative lookup, but it's probably worth some investigation to see if NULL can be used instead.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. 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: afs: Fix delayed allocation of a cell's anonymous key The allocation of a cell's anonymous key is done in a background thread along with other cell setup such as doing a DNS upcall. In the reported bug, this is triggered by afs_parse_source() parsing the device name given to mount() and calling afs_lookup_cell() with the name of the cell. The normal key lookup then tries to use the key description on the anonymous authentication key as the reference for request_key() - but it may not yet be set and so an oops can happen. This has been made more likely to happen by the fix for dynamic lookup failure. Fix this by firstly allocating a reference name and attaching it to the afs_cell record when the record is created. It can share the memory allocation with the cell name (unfortunately it can't just overlap the cell name by prepending it with "afs@" as the cell name already has a '.' prepended for other purposes). This reference name is then passed to request_key(). Secondly, the anon key is now allocated on demand at the point a key is requested in afs_request_key() if it is not already allocated. A mutex is used to prevent multiple allocation for a cell. Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't yet allocated (if we need it) and then the caller can return -ECHILD to drop out of RCU-mode and afs_request_key() can be called. Note that the anonymous key is kind of necessary to make the key lookup cache work as that doesn't currently cache a negative lookup, but it's probably worth some investigation to see if NULL can be used instead.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. 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
the affected interface → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Unspecified
Privileges required
Not stated in the selected CVSS metric
User interaction
Not stated in the selected CVSS metric
Attack complexity
Not stated in the selected CVSS metric
Security boundary
Not stated in the selected CVSS metric
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
Not available from the selected scoring authority.
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.
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2025-2868Linux Kernel: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, die möglicherweise zu einer Denial-of-Service- Bedingung führen oder eine Speicherbeschädigung verursachen können.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0421Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-68289 Référence CVE CVE-2025-68290 https://www.cve.org/CVERecord?id=CVE-2025-68290 Référence CVE CVE-2025-68292 https://www.cve.org/CVERecord?id=CVE-2025-68292 Référence CVE CVE-2025-68293 https://www.cve.org/CVERecord?id=CVE-2025-68293 Référence CVE CVE-2025-68294 https://www.cve.org/CVERecord?id=CVE-2025-68294 Référence CVE CVE-2025-68295 https://www.cve.org/CVERecord?id=CVE-2025-68295 Référence CVE CVE-2025-68296 https://www.cve.org/CVERecord?id=CVE-2025-68296 Référence CVE CVE-2025-68297 https://www.cve.org/CVERecord?id=CVE-2025-68297 Référence CVE CVE-2025-68298 https://www.cve.org/CVERecord?id=CVE-2025-68298 Référence CVE CVE-2025-68299 https://www.cve.org/CVERecord?id=CVE-2025-68299 Référence CVE CVE-2025-68300 https://www.cve.org/CVERecord?id=CVE-2025-68300 Référence CVE CVE-2025-68301 https://www.cve.org/CVERecord?id=CVE-2025-68301 Référence CVE CVE-2025-68302 https://www.cve.org/CVERecord?id=CVE-2025-68302 Référence CVE CVE-2025-68303 https://www.cve.org/CVERecord?id=CVE-2025-68303 Référence CVE CVE-2025-68304 https://www.cve.org/CVERecord?id=CVE-2025-68304 Référence CVE CVE-2025-68305 https://www.cve.org/CVERecord?id=CVE-2025-68305 Référence CVE CVE-2025-68306 https://www.cve.org/CVERecord?id=CVE-2025-68306 Référence CVE CVE-2025-68307 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0397Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-68289 Référence CVE CVE-2025-68290 https://www.cve.org/CVERecord?id=CVE-2025-68290 Référence CVE CVE-2025-68292 https://www.cve.org/CVERecord?id=CVE-2025-68292 Référence CVE CVE-2025-68293 https://www.cve.org/CVERecord?id=CVE-2025-68293 Référence CVE CVE-2025-68294 https://www.cve.org/CVERecord?id=CVE-2025-68294 Référence CVE CVE-2025-68295 https://www.cve.org/CVERecord?id=CVE-2025-68295 Référence CVE CVE-2025-68296 https://www.cve.org/CVERecord?id=CVE-2025-68296 Référence CVE CVE-2025-68297 https://www.cve.org/CVERecord?id=CVE-2025-68297 Référence CVE CVE-2025-68298 https://www.cve.org/CVERecord?id=CVE-2025-68298 Référence CVE CVE-2025-68299 https://www.cve.org/CVERecord?id=CVE-2025-68299 Référence CVE CVE-2025-68300 https://www.cve.org/CVERecord?id=CVE-2025-68300 Référence CVE CVE-2025-68301 https://www.cve.org/CVERecord?id=CVE-2025-68301 Référence CVE CVE-2025-68302 https://www.cve.org/CVERecord?id=CVE-2025-68302 Référence CVE CVE-2025-68303 https://www.cve.org/CVERecord?id=CVE-2025-68303 Référence CVE CVE-2025-68304 https://www.cve.org/CVERecord?id=CVE-2025-68304 Référence CVE CVE-2025-68305 https://www.cve.org/CVERecord?id=CVE-2025-68305 Référence CVE CVE-2025-68306 https://www.cve.org/CVERecord?id=CVE-2025-68306 Référence CVE CVE-2025-68307 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0371Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-68289 Référence CVE CVE-2025-68290 https://www.cve.org/CVERecord?id=CVE-2025-68290 Référence CVE CVE-2025-68292 https://www.cve.org/CVERecord?id=CVE-2025-68292 Référence CVE CVE-2025-68293 https://www.cve.org/CVERecord?id=CVE-2025-68293 Référence CVE CVE-2025-68294 https://www.cve.org/CVERecord?id=CVE-2025-68294 Référence CVE CVE-2025-68295 https://www.cve.org/CVERecord?id=CVE-2025-68295 Référence CVE CVE-2025-68296 https://www.cve.org/CVERecord?id=CVE-2025-68296 Référence CVE CVE-2025-68297 https://www.cve.org/CVERecord?id=CVE-2025-68297 Référence CVE CVE-2025-68298 https://www.cve.org/CVERecord?id=CVE-2025-68298 Référence CVE CVE-2025-68299 https://www.cve.org/CVERecord?id=CVE-2025-68299 Référence CVE CVE-2025-68300 https://www.cve.org/CVERecord?id=CVE-2025-68300 Référence CVE CVE-2025-68301 https://www.cve.org/CVERecord?id=CVE-2025-68301 Référence CVE CVE-2025-68302 https://www.cve.org/CVERecord?id=CVE-2025-68302 Référence CVE CVE-2025-68303 https://www.cve.org/CVERecord?id=CVE-2025-68303 Référence CVE CVE-2025-68304 https://www.cve.org/CVERecord?id=CVE-2025-68304 Référence CVE CVE-2025-68305 https://www.cve.org/CVERecord?id=CVE-2025-68305 Référence CVE CVE-2025-68306 https://www.cve.org/CVERecord?id=CVE-2025-68306 Référence CVE CVE-2025-68307 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0331Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-68289 Référence CVE CVE-2025-68290 https://www.cve.org/CVERecord?id=CVE-2025-68290 Référence CVE CVE-2025-68292 https://www.cve.org/CVERecord?id=CVE-2025-68292 Référence CVE CVE-2025-68293 https://www.cve.org/CVERecord?id=CVE-2025-68293 Référence CVE CVE-2025-68294 https://www.cve.org/CVERecord?id=CVE-2025-68294 Référence CVE CVE-2025-68295 https://www.cve.org/CVERecord?id=CVE-2025-68295 Référence CVE CVE-2025-68296 https://www.cve.org/CVERecord?id=CVE-2025-68296 Référence CVE CVE-2025-68297 https://www.cve.org/CVERecord?id=CVE-2025-68297 Référence CVE CVE-2025-68298 https://www.cve.org/CVERecord?id=CVE-2025-68298 Référence CVE CVE-2025-68299 https://www.cve.org/CVERecord?id=CVE-2025-68299 Référence CVE CVE-2025-68300 https://www.cve.org/CVERecord?id=CVE-2025-68300 Référence CVE CVE-2025-68301 https://www.cve.org/CVERecord?id=CVE-2025-68301 Référence CVE CVE-2025-68302 https://www.cve.org/CVERecord?id=CVE-2025-68302 Référence CVE CVE-2025-68303 https://www.cve.org/CVERecord?id=CVE-2025-68303 Référence CVE CVE-2025-68304 https://www.cve.org/CVERecord?id=CVE-2025-68304 Référence CVE CVE-2025-68305 https://www.cve.org/CVERecord?id=CVE-2025-68305 Référence CVE CVE-2025-68306 https://www.cve.org/CVERecord?id=CVE-2025-68306 Référence CVE CVE-2025-68307 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.
Fix not verified
Affected
fa4ccdccf1489a6dac4369a8c69f11b455b3355c < bd18d2cbc9377c6b270c0b7ea44b0e6ed1d99c07; 7e33b15d5a6578a99ebf189cea34983270ae92dd < 5613bde937dfac6725e9c3fc766b9d6b8481e55b; 330e2c514823008b22e6afd2055715bc46dd8d55 < d27c71257825dced46104eefe42e4d9964bd032e; 6.17.9 < 6.17.11
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 16 Dec 2025 · Last source change 3 Aug 2026, 09:32 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceUnavailable
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-2025-203781
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD not scheduled

Missing structured fields: CVSS base score, CWE classification. Missing data is not evidence of low risk; review the primary advisory.

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
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-2025-68299 · cve.blacktree.nl