CVE-2025-38546: atm: clip: Fix memory leak of struct clip_vcc.

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-08-16 · updated 2026-06-17
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: atm: clip: Fix memory leak of struct clip_vcc. ioctl(ATMARP_MKIP) allocates struct clip_vcc and set it to vcc->user_back. The code assumes that vcc_destroy_socket() passes NULL skb to vcc->push() when the socket is close()d, and then clip_push() frees clip_vcc. However, ioctl(ATMARPD_CTRL) sets NULL to vcc->push() in atm_init_atmarp(), resulting in memory leak. Let's serialise two ioctl() by lock_sock() and check vcc->push() in atm_init_atmarp() to prevent memleak.

Affected products

Debian Linux: 11.0
Linux kernel: from 2.6.13 before 5.4.296; from 5.5 before 5.10.240; from 5.11 before 5.15.189; from 5.16 before 6.1.146; from 6.2 before 6.6.99; from 6.7 before 6.12.39 — fixed in 5.10.240, 5.15.189, 5.4.296, 6.1.146, 6.12.39, 6.15.7

How to fix

Upgrade to a fixed version: Linux kernel 5.10.240, 5.15.189, 5.4.296, 6.1.146. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2025-38546 or the next vulnerability affects your stack