7.8High
CVE-2025-40139
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.
What this means for your business
- An attacker can use it only with access to the machine itself, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 4% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 7.8 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2025-11-12
- Last modified
- 2026-09-02
- Sources
- NVD
References
- https://git.kernel.org/stable/c/0736993bfe5c7a9c744ae3fac62d769dfdae54e1
- https://git.kernel.org/stable/c/5a2fccc4b32c13ddde3676f9e15e1a9baa7d6fde
- https://git.kernel.org/stable/c/80d1fd39f4e37d836655e9f7ffccaf78925049bf
- https://git.kernel.org/stable/c/935d783e5de9b64587f3adb25641dd8385e64ddb
- https://git.kernel.org/stable/c/956c57daba55cf9ed25d9f2512883b8a1a927599