BlackTreeIndependent security intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-23201High confidence

ceph: fix oops due to invalid pointer for kfree() in parse_longname()

Linux · Linux

5.5MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
Distribution package intelligence

Ubuntu vendor package status

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

20 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 archivelinuxAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-awsAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azureAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-fdeAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-nvidiaAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcpAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeopAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-ibmAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatencyAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidiaAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-lowlatencyAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-tegraAffected, 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 8 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracleAffected, 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspiAffected, 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 8 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 8 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 8 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 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-xilinxAffected, 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 8 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-2026-5844

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 actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: ceph: fix oops due to invalid pointer for kfree() in parse_longname() This fixes a kernel oops when reading ceph snapshot directories (.snap), for example by simply running `ls /mnt/my_ceph/.snap`. The variable str is guarded by __free(kfree), but advanced by one for skipping the initial '_' in snapshot names. Thus, kfree() is called with an invalid pointer. This patch removes the need for advancing the pointer so kfree() is called with correct memory pointer. Steps to reproduce: 1. Create snapshots on a cephfs volume (I've 63 snaps in my testcase) 2. Add cephfs mount to fstab $ echo "samba-fileserver@.files=/volumes/datapool/stuff/3461082b-ecc9-4e82-8549-3fd2590d3fb6 /mnt/test/stuff ceph acl,noatime,_netdev 0 0" >> /etc/fstab 3. Reboot the system $ systemctl reboot 4. Check if it's really mounted $ mount | grep stuff 5. List snapshots (expected 63 snapshots on my system) $ ls /mnt/test/stuff/.snap Now ls hangs forever and the kernel log shows the oops.

What

In the Linux kernel, the following vulnerability has been resolved: ceph: fix oops due to invalid pointer for kfree() in parse_longname() This fixes a kernel oops when reading ceph snapshot directories (.snap), for example by simply running `ls /mnt/my_ceph/.snap`. The variable str is guarded by __free(kfree), but advanced by one for skipping the initial '_' in snapshot names. Thus, kfree() is called with an invalid pointer. This patch removes the need for advancing the pointer so kfree() is called with correct memory pointer. Steps to reproduce: 1. Create snapshots on a cephfs volume (I've 63 snaps in my testcase) 2. Add cephfs mount to fstab $ echo "samba-fileserver@.files=/volumes/datapool/stuff/3461082b-ecc9-4e82-8549-3fd2590d3fb6 /mnt/test/stuff ceph acl,noatime,_netdev 0 0" >> /etc/fstab 3. Reboot the system $ systemctl reboot 4. Check if it's really mounted $ mount | grep stuff 5. List snapshots (expected 63 snapshots on my system) $ ls /mnt/test/stuff/.snap Now ls hangs forever and the kernel log shows the oops.

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: ceph: fix oops due to invalid pointer for kfree() in parse_longname() This fixes a kernel oops when reading ceph snapshot directories (.snap), for example by simply running `ls /mnt/my_ceph/.snap`. The variable str is guarded by __free(kfree), but advanced by one for skipping the initial '_' in snapshot names. Thus, kfree() is called with an invalid pointer. This patch removes the need for advancing the pointer so kfree() is called with correct memory pointer. Steps to reproduce: 1. Create snapshots on a cephfs volume (I've 63 snaps in my testcase) 2. Add cephfs mount to fstab $ echo "samba-fileserver@.files=/volumes/datapool/stuff/3461082b-ecc9-4e82-8549-3fd2590d3fb6 /mnt/test/stuff ceph acl,noatime,_netdev 0 0" >> /etc/fstab 3. Reboot the system $ systemctl reboot 4. Check if it's really mounted $ mount | grep stuff 5. List snapshots (expected 63 snapshots on my system) $ ls /mnt/test/stuff/.snap Now ls hangs forever and the kernel log shows the oops.

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: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.
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-2026-0421Linux 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-0546Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2026-23004 Référence CVE CVE-2026-23030 https://www.cve.org/CVERecord?id=CVE-2026-23030 Référence CVE CVE-2026-23047 https://www.cve.org/CVERecord?id=CVE-2026-23047 Référence CVE CVE-2026-23103 https://www.cve.org/CVERecord?id=CVE-2026-23103 Référence CVE CVE-2026-23120 https://www.cve.org/CVERecord?id=CVE-2026-23120 Référence CVE CVE-2026-23136 https://www.cve.org/CVERecord?id=CVE-2026-23136 Référence CVE CVE-2026-23140 https://www.cve.org/CVERecord?id=CVE-2026-23140 Référence CVE CVE-2026-23187 https://www.cve.org/CVERecord?id=CVE-2026-23187 Référence CVE CVE-2026-23193 https://www.cve.org/CVERecord?id=CVE-2026-23193 Référence CVE CVE-2026-23201 https://www.cve.org/CVERecord?id=CVE-2026-23201 Référence CVE CVE-2026-23204 https://www.cve.org/CVERecord?id=CVE-2026-23204 Référence CVE CVE-2026-23215 https://www.cve.org/CVERecord?id=CVE-2026-23215 Référence CVE CVE-2026-23216 https://www.cve.org/CVERecord?id=CVE-2026-23216 Référence CVE CVE-2026-23231 https://www.cve.org/CVERecord?id=CVE-2026-23231 Référence CVE CVE-2026-23242 https://www.cve.org/CVERecord?id=CVE-2026-23242 Référence CVE CVE-2026-23243 https://www.cve.org/CVERecord?id=CVE-2026-23243 Référence CVE CVE-2026-23255 https://www.cve.org/CVERecord?id=CVE-2026-23255 Référence CVE CVE-2026-23259 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0497Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2026-23136 Référence CVE CVE-2026-23138 https://www.cve.org/CVERecord?id=CVE-2026-23138 Référence CVE CVE-2026-23140 https://www.cve.org/CVERecord?id=CVE-2026-23140 Référence CVE CVE-2026-23154 https://www.cve.org/CVERecord?id=CVE-2026-23154 Référence CVE CVE-2026-23157 https://www.cve.org/CVERecord?id=CVE-2026-23157 Référence CVE CVE-2026-23169 https://www.cve.org/CVERecord?id=CVE-2026-23169 Référence CVE CVE-2026-23187 https://www.cve.org/CVERecord?id=CVE-2026-23187 Référence CVE CVE-2026-23191 https://www.cve.org/CVERecord?id=CVE-2026-23191 Référence CVE CVE-2026-23193 https://www.cve.org/CVERecord?id=CVE-2026-23193 Référence CVE CVE-2026-23201 https://www.cve.org/CVERecord?id=CVE-2026-23201 Référence CVE CVE-2026-23202 https://www.cve.org/CVERecord?id=CVE-2026-23202 Référence CVE CVE-2026-23204 https://www.cve.org/CVERecord?id=CVE-2026-23204 Référence CVE CVE-2026-23207 https://www.cve.org/CVERecord?id=CVE-2026-23207 Référence CVE CVE-2026-23209 https://www.cve.org/CVERecord?id=CVE-2026-23209 Référence CVE CVE-2026-23215 https://www.cve.org/CVERecord?id=CVE-2026-23215 Référence CVE CVE-2026-23216 https://www.cve.org/CVERecord?id=CVE-2026-23216 Référence CVE CVE-2026-23231 https://www.cve.org/CVERecord?id=CVE-2026-23231 Référence CVE CVE-2026-23239 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0192Multiples vulnérabilités dans le noyau Linux de Debian

d?id=CVE-2026-23187 Référence CVE CVE-2026-23188 https://www.cve.org/CVERecord?id=CVE-2026-23188 Référence CVE CVE-2026-23189 https://www.cve.org/CVERecord?id=CVE-2026-23189 Référence CVE CVE-2026-23190 https://www.cve.org/CVERecord?id=CVE-2026-23190 Référence CVE CVE-2026-23191 https://www.cve.org/CVERecord?id=CVE-2026-23191 Référence CVE CVE-2026-23193 https://www.cve.org/CVERecord?id=CVE-2026-23193 Référence CVE CVE-2026-23198 https://www.cve.org/CVERecord?id=CVE-2026-23198 Référence CVE CVE-2026-23199 https://www.cve.org/CVERecord?id=CVE-2026-23199 Référence CVE CVE-2026-23200 https://www.cve.org/CVERecord?id=CVE-2026-23200 Référence CVE CVE-2026-23201 https://www.cve.org/CVERecord?id=CVE-2026-23201 Référence CVE CVE-2026-23202 https://www.cve.org/CVERecord?id=CVE-2026-23202 Référence CVE CVE-2026-23204 https://www.cve.org/CVERecord?id=CVE-2026-23204 Référence CVE CVE-2026-23205 https://www.cve.org/CVERecord?id=CVE-2026-23205 Référence CVE CVE-2026-23206 https://www.cve.org/CVERecord?id=CVE-2026-23206 Référence CVE CVE-2026-23209 https://www.cve.org/CVERecord?id=CVE-2026-23209 Référence CVE CVE-2026-23213 https://www.cve.org/CVERecord?id=CVE-2026-23213 Référence CVE CVE-2026-23214 https://www.cve.org/CVERecord?id=CVE-2026-23214 Référence CVE CVE-2026-23215 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
bb80f7618832d26f7e395f52f82b1dac76223e5f < 8c9af7339de419819cfc641d551675d38ff99abf; 101841c38346f4ca41dc1802c867da990ffb32eb < e258ed369c9e04caa7d2fd49785d753ae4034cb6; 101841c38346f4ca41dc1802c867da990ffb32eb < bc8dedae022ce3058659c3addef3ec4b41d15e00; 3145b2b11492d61c512bbc59660bb823bc757f48; 493479af8af3ab907f49e99323777d498a4fbd2b; 6.12.42 < 6.12.70; 6.15.10 < 6.16; 6.16.1 < 6.17
Fixed
< 6.17; 6.12.70 ≤ 6.12.*; 6.18.10 ≤ 6.18.*; 6.19 ≤ *
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 14 Feb 2026 · Last source change 23 May 2026, 16:04 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-2026-5844
Product sourceCNA
Remediation sourceCVE/CNA references
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
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-2026-23201 · cve.blacktree.nl