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Full vulnerability report · 2024
CVE-2023-52836High confidence

locking/ww_mutex/test: Fix potential workqueue corruption

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.

2 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-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-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
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
SSA-613116 · CSAF 2.0 · revision 3 · interimSiemens ProductCERTSSA-613116: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.1
3 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • RUGGEDCOM RST2428P (6GK6242-6PA00)
  • SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family
  • SCALANCE XCM-/XRM-/XCH-/XRH-300 family
Summary
In the Linux kernel, the following vulnerability has been resolved: locking/ww_mutex/test: Fix potential workqueue corruption
Remediation
No remediation text is recorded.
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-2023-59550

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: locking/ww_mutex/test: Fix potential workqueue corruption In some cases running with the test-ww_mutex code, I was seeing odd behavior where sometimes it seemed flush_workqueue was returning before all the work threads were finished. Often this would cause strange crashes as the mutexes would be freed while they were being used. Looking at the code, there is a lifetime problem as the controlling thread that spawns the work allocates the "struct stress" structures that are passed to the workqueue threads. Then when the workqueue threads are finished, they free the stress struct that was passed to them. Unfortunately the workqueue work_struct node is in the stress struct. Which means the work_struct is freed before the work thread returns and while flush_workqueue is waiting. It seems like a better idea to have the controlling thread both allocate and free the stress structures, so that we can be sure we don't corrupt the workqueue by freeing the structure prematurely. So this patch reworks the test to do so, and with this change I no longer see the early flush_workqueue returns.

What

In the Linux kernel, the following vulnerability has been resolved: locking/ww_mutex/test: Fix potential workqueue corruption In some cases running with the test-ww_mutex code, I was seeing odd behavior where sometimes it seemed flush_workqueue was returning before all the work threads were finished. Often this would cause strange crashes as the mutexes would be freed while they were being used. Looking at the code, there is a lifetime problem as the controlling thread that spawns the work allocates the "struct stress" structures that are passed to the workqueue threads. Then when the workqueue threads are finished, they free the stress struct that was passed to them. Unfortunately the workqueue work_struct node is in the stress struct. Which means the work_struct is freed before the work thread returns and while flush_workqueue is waiting. It seems like a better idea to have the controlling thread both allocate and free the stress structures, so that we can be sure we don't corrupt the workqueue by freeing the structure prematurely. So this patch reworks the test to do so, and with this change I no longer see the early flush_workqueue returns.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

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

What

In the Linux kernel, the following vulnerability has been resolved: locking/ww_mutex/test: Fix potential workqueue corruption In some cases running with the test-ww_mutex code, I was seeing odd behavior where sometimes it seemed flush_workqueue was returning before all the work threads were finished. Often this would cause strange crashes as the mutexes would be freed while they were being used. Looking at the code, there is a lifetime problem as the controlling thread that spawns the work allocates the "struct stress" structures that are passed to the workqueue threads. Then when the workqueue threads are finished, they free the stress struct that was passed to them. Unfortunately the workqueue work_struct node is in the stress struct. Which means the work_struct is freed before the work thread returns and while flush_workqueue is waiting. It seems like a better idea to have the controlling thread both allocate and free the stress structures, so that we can be sure we don't corrupt the workqueue by freeing the structure prematurely. So this patch reworks the test to do so, and with this change I no longer see the early flush_workqueue returns.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

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

02

Exploit reality and attack path

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

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

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

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

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

Likely attack path
local access → Out-of-bounds Write → disrupt the affected service
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-787 ↗

CWE-787: Out-of-bounds Write. The product writes data past the end, or before the beginning, of the intended buffer.

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.
Denial of serviceCWE-787
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2024-1197Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service und unspezifische Angriffe

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

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0677Multiples vulnérabilités dans les produits Siemens

d?id=CVE-2023-52806 Référence CVE CVE-2023-52809 https://www.cve.org/CVERecord?id=CVE-2023-52809 Référence CVE CVE-2023-52810 https://www.cve.org/CVERecord?id=CVE-2023-52810 Référence CVE CVE-2023-52813 https://www.cve.org/CVERecord?id=CVE-2023-52813 Référence CVE CVE-2023-52817 https://www.cve.org/CVERecord?id=CVE-2023-52817 Référence CVE CVE-2023-52818 https://www.cve.org/CVERecord?id=CVE-2023-52818 Référence CVE CVE-2023-52819 https://www.cve.org/CVERecord?id=CVE-2023-52819 Référence CVE CVE-2023-52832 https://www.cve.org/CVERecord?id=CVE-2023-52832 Référence CVE CVE-2023-52835 https://www.cve.org/CVERecord?id=CVE-2023-52835 Référence CVE CVE-2023-52836 https://www.cve.org/CVERecord?id=CVE-2023-52836 Référence CVE CVE-2023-52838 https://www.cve.org/CVERecord?id=CVE-2023-52838 Référence CVE CVE-2023-52840 https://www.cve.org/CVERecord?id=CVE-2023-52840 Référence CVE CVE-2023-52843 https://www.cve.org/CVERecord?id=CVE-2023-52843 Référence CVE CVE-2023-52845 https://www.cve.org/CVERecord?id=CVE-2023-52845 Référence CVE CVE-2023-52847 https://www.cve.org/CVERecord?id=CVE-2023-52847 Référence CVE CVE-2023-52853 https://www.cve.org/CVERecord?id=CVE-2023-52853 Référence CVE CVE-2023-52855 https://www.cve.org/CVERecord?id=CVE-2023-52855 Référence CVE CVE-2023-52858 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0717Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-52821 Référence CVE CVE-2023-52825 https://www.cve.org/CVERecord?id=CVE-2023-52825 Référence CVE CVE-2023-52826 https://www.cve.org/CVERecord?id=CVE-2023-52826 Référence CVE CVE-2023-52827 https://www.cve.org/CVERecord?id=CVE-2023-52827 Référence CVE CVE-2023-52829 https://www.cve.org/CVERecord?id=CVE-2023-52829 Référence CVE CVE-2023-52832 https://www.cve.org/CVERecord?id=CVE-2023-52832 Référence CVE CVE-2023-52833 https://www.cve.org/CVERecord?id=CVE-2023-52833 Référence CVE CVE-2023-52834 https://www.cve.org/CVERecord?id=CVE-2023-52834 Référence CVE CVE-2023-52835 https://www.cve.org/CVERecord?id=CVE-2023-52835 Référence CVE CVE-2023-52836 https://www.cve.org/CVERecord?id=CVE-2023-52836 Référence CVE CVE-2023-52837 https://www.cve.org/CVERecord?id=CVE-2023-52837 Référence CVE CVE-2023-52838 https://www.cve.org/CVERecord?id=CVE-2023-52838 Référence CVE CVE-2023-52840 https://www.cve.org/CVERecord?id=CVE-2023-52840 Référence CVE CVE-2023-52841 https://www.cve.org/CVERecord?id=CVE-2023-52841 Référence CVE CVE-2023-52842 https://www.cve.org/CVERecord?id=CVE-2023-52842 Référence CVE CVE-2023-52843 https://www.cve.org/CVERecord?id=CVE-2023-52843 Référence CVE CVE-2023-52844 https://www.cve.org/CVERecord?id=CVE-2023-52844 Référence CVE CVE-2023-52845 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0693Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-52821 Référence CVE CVE-2023-52825 https://www.cve.org/CVERecord?id=CVE-2023-52825 Référence CVE CVE-2023-52826 https://www.cve.org/CVERecord?id=CVE-2023-52826 Référence CVE CVE-2023-52827 https://www.cve.org/CVERecord?id=CVE-2023-52827 Référence CVE CVE-2023-52829 https://www.cve.org/CVERecord?id=CVE-2023-52829 Référence CVE CVE-2023-52832 https://www.cve.org/CVERecord?id=CVE-2023-52832 Référence CVE CVE-2023-52833 https://www.cve.org/CVERecord?id=CVE-2023-52833 Référence CVE CVE-2023-52834 https://www.cve.org/CVERecord?id=CVE-2023-52834 Référence CVE CVE-2023-52835 https://www.cve.org/CVERecord?id=CVE-2023-52835 Référence CVE CVE-2023-52836 https://www.cve.org/CVERecord?id=CVE-2023-52836 Référence CVE CVE-2023-52837 https://www.cve.org/CVERecord?id=CVE-2023-52837 Référence CVE CVE-2023-52838 https://www.cve.org/CVERecord?id=CVE-2023-52838 Référence CVE CVE-2023-52840 https://www.cve.org/CVERecord?id=CVE-2023-52840 Référence CVE CVE-2023-52841 https://www.cve.org/CVERecord?id=CVE-2023-52841 Référence CVE CVE-2023-52842 https://www.cve.org/CVERecord?id=CVE-2023-52842 Référence CVE CVE-2023-52843 https://www.cve.org/CVERecord?id=CVE-2023-52843 Référence CVE CVE-2023-52844 https://www.cve.org/CVERecord?id=CVE-2023-52844 Référence CVE CVE-2023-52845 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0632Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-52821 Référence CVE CVE-2023-52825 https://www.cve.org/CVERecord?id=CVE-2023-52825 Référence CVE CVE-2023-52826 https://www.cve.org/CVERecord?id=CVE-2023-52826 Référence CVE CVE-2023-52827 https://www.cve.org/CVERecord?id=CVE-2023-52827 Référence CVE CVE-2023-52829 https://www.cve.org/CVERecord?id=CVE-2023-52829 Référence CVE CVE-2023-52832 https://www.cve.org/CVERecord?id=CVE-2023-52832 Référence CVE CVE-2023-52833 https://www.cve.org/CVERecord?id=CVE-2023-52833 Référence CVE CVE-2023-52834 https://www.cve.org/CVERecord?id=CVE-2023-52834 Référence CVE CVE-2023-52835 https://www.cve.org/CVERecord?id=CVE-2023-52835 Référence CVE CVE-2023-52836 https://www.cve.org/CVERecord?id=CVE-2023-52836 Référence CVE CVE-2023-52837 https://www.cve.org/CVERecord?id=CVE-2023-52837 Référence CVE CVE-2023-52838 https://www.cve.org/CVERecord?id=CVE-2023-52838 Référence CVE CVE-2023-52840 https://www.cve.org/CVERecord?id=CVE-2023-52840 Référence CVE CVE-2023-52841 https://www.cve.org/CVERecord?id=CVE-2023-52841 Référence CVE CVE-2023-52842 https://www.cve.org/CVERecord?id=CVE-2023-52842 Référence CVE CVE-2023-52843 https://www.cve.org/CVERecord?id=CVE-2023-52843 Référence CVE CVE-2023-52844 https://www.cve.org/CVERecord?id=CVE-2023-52844 Référence CVE CVE-2023-52845 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
2a0c11282881875dc44f166a20eedf0d866dd0ef < d4d37c9e6a4dbcca958dabd99216550525c7e389; 2a0c11282881875dc44f166a20eedf0d866dd0ef < d8267cabbe1bed15ccf8b0e684c528bf8eeef715; 2a0c11282881875dc44f166a20eedf0d866dd0ef < dcd85e3c929368076a7592b27f541e0da8b427f5; 2a0c11282881875dc44f166a20eedf0d866dd0ef < 9ed2d68b3925145f5f51c46559484881d6082f75; 2a0c11282881875dc44f166a20eedf0d866dd0ef < e89d0ed45a419c485bae999426ecf92697cbdda3; 2a0c11282881875dc44f166a20eedf0d866dd0ef < c56df79d68677cf062da1b6e3b33e74299a92dfc; 2a0c11282881875dc44f166a20eedf0d866dd0ef < e36407713163363e65566e7af0abe207d5f59a0c; 2a0c11282881875dc44f166a20eedf0d866dd0ef < 304a2c4aad0fff887ce493e4197bf9cbaf394479
Fixed
< 4.11; 4.14.331 ≤ 4.14.*; 4.19.300 ≤ 4.19.*; 5.4.262 ≤ 5.4.*; 5.10.202 ≤ 5.10.*; 5.15.140 ≤ 5.15.*; 6.1.64 ≤ 6.1.*; 6.5.13 ≤ 6.5.*
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 21 May 2024 · Last source change 11 May 2026, 19:33 UTC · CWE-787 · Out-of-bounds Write

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-2023-59550
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
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2023-59550↗Vendor CSAF · Siemens ProductCERT↗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.
Free version - for non-commercial use only.CVE-2023-52836 · cve.blacktree.nl