CVE-2025-40139

smc: Use __sk_dst_get() and dst_dev_rcu() in in smc_clc_prfx_set().

HIGH
7.8
CVSS Score
Published: November 12, 2025 at 10:23 AM UTC
Updated: October 19, 2026 at 09:10 PM UTC
1 product affected across 1 vendorLinux Kernel

Using Linux by Linux?

Get instant alerts when new vulnerabilities affect Linux - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.8
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.11a046d57da19f812216f393e7c535f5858f793ac3
Vendor states this is fixed in 0736993bfe5c7a9c744ae3fac62d769dfdae54e1 (fixed)
Vendor states this is fixed in 5a2fccc4b32c13ddde3676f9e15e1a9baa7d6fde (fixed)
Vendor states this is fixed in 80d1fd39f4e37d836655e9f7ffccaf78925049bf (fixed)
Vendor states this is fixed in 935d783e5de9b64587f3adb25641dd8385e64ddb (fixed)
Vendor states this is fixed in 956c57daba55cf9ed25d9f2512883b8a1a927599 (fixed)
Vendor states this is fixed in 4.11 (unaffected)
Vendor states this is fixed in 6.1.187 (unaffected)
Vendor states this is fixed in 6.12.108 (unaffected)
Vendor states this is fixed in 6.17.3 (unaffected)
Vendor states this is fixed in 6.18 (unaffected)
Vendor states this is fixed in 6.6.156 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusDEFERRED

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card