CVE-2025-40139
smc: Use __sk_dst_get() and dst_dev_rcu() in in smc_clc_prfx_set().
Description
In the Linux kernel, the following vulnerability has been resolved: smc: Use __sk_dst_get() and dst_dev_rcu() in in smc_clc_prfx_set(). smc_clc_prfx_set() is called during connect() and not under RCU nor RTNL. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dev_dst_rcu() under rcu_read_lock() after kernel_getsockname(). Note that the returned value of smc_clc_prfx_set() is not used in the caller. While at it, we change the 1st arg of smc_clc_prfx_set[46]_rcu() not to touch dst there.
INFO
Published Date :
Nov. 12, 2025, 11:15 a.m.
Last Modified :
Sept. 2, 2026, 1:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Apply the Linux kernel patch.
- Update the Linux kernel.
- Modify smc_clc_prfx_set to use RCU.
- Ensure kernel_getsockname is called.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-40139.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-40139 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-40139
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-40139 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-40139 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 02, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2025/40xxx/CVE-2025-40139.json">CVE-2025-40139</a> Added Reference https://git.kernel.org/stable/c/0736993bfe5c7a9c744ae3fac62d769dfdae54e1 Added Reference https://git.kernel.org/stable/c/5a2fccc4b32c13ddde3676f9e15e1a9baa7d6fde Added Reference https://git.kernel.org/stable/c/80d1fd39f4e37d836655e9f7ffccaf78925049bf Added Reference https://git.kernel.org/stable/c/935d783e5de9b64587f3adb25641dd8385e64ddb Added Reference https://git.kernel.org/stable/c/956c57daba55cf9ed25d9f2512883b8a1a927599 Removed Reference https://git.kernel.org/stable/c/0736993bfe5c7a9c744ae3fac62d769dfdae54e1 Removed Reference https://git.kernel.org/stable/c/935d783e5de9b64587f3adb25641dd8385e64ddb -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 30, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'a046d57da19f812216f393e7c535f5858f793ac3', 'lessThan': '0736993bfe5c7a9c744ae3fac62d769dfdae54e1', 'versionType': 'git'}, {'status': 'affected', 'version': 'a046d57da19f812216f393e7c535f5858f793ac3', 'lessThan': '935d783e5de9b64587f3adb25641dd8385e64ddb', 'versionType': 'git'}], 'programFiles': ['net/smc/smc_clc.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.11'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.11', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.17.3', 'versionType': 'semver', 'lessThanOrEqual': '6.17.*'}, {'status': 'unaffected', 'version': '6.18', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/smc/smc_clc.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Nov. 12, 2025
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: smc: Use __sk_dst_get() and dst_dev_rcu() in in smc_clc_prfx_set(). smc_clc_prfx_set() is called during connect() and not under RCU nor RTNL. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dev_dst_rcu() under rcu_read_lock() after kernel_getsockname(). Note that the returned value of smc_clc_prfx_set() is not used in the caller. While at it, we change the 1st arg of smc_clc_prfx_set[46]_rcu() not to touch dst there. Added Reference https://git.kernel.org/stable/c/0736993bfe5c7a9c744ae3fac62d769dfdae54e1 Added Reference https://git.kernel.org/stable/c/935d783e5de9b64587f3adb25641dd8385e64ddb