Linux Kernel up to 6.17-rc5 state_show use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.152/6.6.106/6.12.47/6.16.7/6.17-rc5 and classified as critical. This affects the function state_show. The manipulation results in use after free. This vulnerability is reported as CVE-2025-39877. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.152/6.6.106/6.12.47/6.16.7/6.17-rc5. Affected is the function state_show. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs: fix use-after-free in state_show() state_show() reads kdamond->damon_ctx without holding damon_sysfs_lock. This allows a use-after-free race: CPU 0 CPU 1 ----- ----- state_show() damon_sysfs_turn_damon_on() ctx = kdamond->damon_ctx; mutex_lock(&damon_sysfs_lock); damon_destroy_ctx(kdamond->damon_ctx); kdamond->damon_ctx = NULL; mutex_unlock(&damon_sysfs_lock); damon_is_running(ctx); /* ctx is freed */ mutex_lock(&ctx->kdamond_lock); /* UAF */ (The race can also occur with damon_sysfs_kdamonds_rm_dirs() and damon_sysfs_kdamond_release(), which free or replace the context under damon_sysfs_lock.) Fix by taking damon_sysfs_lock before dereferencing the context, mirroring the locking used in pid_show(). The bug has existed since state_show() first accessed kdamond->damon_ctx.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2025-39877 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 02/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 265875 (Linux Distros Unpatched Vulnerability : CVE-2025-39877), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.153, 6.6.107, 6.12.48, 6.16.8 or 6.17-rc6 eliminates this vulnerability. Applying the patch 3858c44341ad49dc7544b19cc9f9ecffaa7cc50e/60d7a3d2b985a395318faa1d88da6915fad11c19/26d29b2ac87a2989071755f9828ebf839b560d4c/4e87f461d61959647464a94d11ae15c011be58ce/3260a3f0828e06f5f13fac69fb1999a6d60d9cff is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (265875) and CERT Bund (WID-SEC-2025-2107). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • Dell Secure Connect Gateway
  • IBM QRadar SIEM
  • Dell NetWorker

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 265875
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39877

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.153/6.6.107/6.12.48/6.16.8/6.17-rc6
Patch: 3858c44341ad49dc7544b19cc9f9ecffaa7cc50e/60d7a3d2b985a395318faa1d88da6915fad11c19/26d29b2ac87a2989071755f9828ebf839b560d4c/4e87f461d61959647464a94d11ae15c011be58ce/3260a3f0828e06f5f13fac69fb1999a6d60d9cff

Timelineinfo

04/16/2025 CVE reserved
09/23/2025 +160 days Advisory disclosed
09/23/2025 +0 days VulDB entry created
02/16/2026 +146 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39877 (🔒)
GCVE (CVE): GCVE-0-2025-39877
GCVE (VulDB): GCVE-100-325602
CERT Bund: WID-SEC-2025-2107 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/23/2025 08:36
Updated: 02/16/2026 09:39
Changes: 09/23/2025 08:36 (58), 09/28/2025 18:35 (2), 12/01/2025 19:25 (7), 01/12/2026 04:53 (1), 01/21/2026 01:40 (11), 02/09/2026 08:13 (1), 02/16/2026 09:39 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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