Linux Kernel up to 6.17.5 vsock_assign_transport deadlock

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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.17.5. This impacts the function vsock_assign_transport. Executing a manipulation can lead to deadlock. This vulnerability appears as CVE-2025-40231. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.17.5. This vulnerability affects the function vsock_assign_transport. The manipulation with an unknown input leads to a deadlock vulnerability. The CWE definition for the vulnerability is CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: vsock: fix lock inversion in vsock_assign_transport() Syzbot reported a potential lock inversion deadlock between vsock_register_mutex and sk_lock-AF_VSOCK when vsock_linger() is called. The issue was introduced by commit 687aa0c5581b ("vsock: Fix transport_* TOCTOU") which added vsock_register_mutex locking in vsock_assign_transport() around the transport->release() call, that can call vsock_linger(). vsock_assign_transport() can be called with sk_lock held. vsock_linger() calls sk_wait_event() that temporarily releases and re-acquires sk_lock. During this window, if another thread hold vsock_register_mutex while trying to acquire sk_lock, a circular dependency is created. Fix this by releasing vsock_register_mutex before calling transport->release() and vsock_deassign_transport(). This is safe because we don't need to hold vsock_register_mutex while releasing the old transport, and we ensure the new transport won't disappear by obtaining a module reference first via try_module_get().

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-40231 since 04/16/2025. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 277479 (Linux Distros Unpatched Vulnerability : CVE-2025-40231), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.246, 5.15.196, 6.1.158, 6.6.115, 6.12.56 or 6.17.6 eliminates this vulnerability. Applying the patch ce4f856c64f0bc30e29302a0ce41f4295ca391c5/09bba278ccde25a14b6e5088a9e65a8717d0cccf/b44182c116778feaa05da52a426aeb9da1878dcf/42ed0784d11adebf748711e503af0eb9f1e6d81d/251caee792a21eb0b781aab91362b422c945e162/a2a4346eea8b4cb75037dbcb20b98cb454324f80/f7c877e7535260cc7a21484c994e8ce7e8cb6780 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 (277479) and CERT Bund (WID-SEC-2025-2747). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • Microsoft Azure Linux

Productinfo

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Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.6

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Deadlock
CWE: CWE-833 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 277479
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-40231

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.246/5.15.196/6.1.158/6.6.115/6.12.56/6.17.6
Patch: ce4f856c64f0bc30e29302a0ce41f4295ca391c5/09bba278ccde25a14b6e5088a9e65a8717d0cccf/b44182c116778feaa05da52a426aeb9da1878dcf/42ed0784d11adebf748711e503af0eb9f1e6d81d/251caee792a21eb0b781aab91362b422c945e162/a2a4346eea8b4cb75037dbcb20b98cb454324f80/f7c877e7535260cc7a21484c994e8ce7e8cb6780

Timelineinfo

04/16/2025 CVE reserved
12/04/2025 +232 days Advisory disclosed
12/04/2025 +0 days VulDB entry created
02/23/2026 +81 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-40231 (🔒)
GCVE (CVE): GCVE-0-2025-40231
GCVE (VulDB): GCVE-100-334288
CERT Bund: WID-SEC-2025-2747 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 12/04/2025 17:29
Updated: 02/23/2026 13:45
Changes: 12/04/2025 17:29 (58), 12/07/2025 00:24 (2), 01/05/2026 01:36 (7), 02/23/2026 13:45 (1)
Complete: 🔍
Cache ID: 216::103

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