Review reviewHigh

CVE-2025-40168

Linux

In the Linux kernel, the following vulnerability has been resolved: smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match(). smc_clc_prfx_match() is called from smc_listen_work() and not under RCU nor RTNL. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dst_dev_rcu(). Note that the returned value of smc_clc_prfx_match() is not used in the caller.

CVSS
8.1
EPSS
-
- percentile
CISA KEV
Not listed
Published
2025.11.12
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 8.1

Vulnerability overview

In the Linux kernel, the following vulnerability has been resolved: smc: Use __sk_dst_get() and dst_dev_rcu() in smc_clc_prfx_match(). smc_clc_prfx_match() is called from smc_listen_work() and not under RCU nor RTNL. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dst_dev_rcu(). Note that the returned value of smc_clc_prfx_match() is not used in the caller.

Affected product and versions

Product
Linux
Affected versions
>= a046d57da19f812216f393e7c535f5858f793ac3 < d26e80f7fb62d77757b67a1b94e4ac756bc9c658, >= a046d57da19f812216f393e7c535f5858f793ac3 < 235f81045c008169cc4e1955b4a64e118eebe61b, >= 4.11
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Not available