CVE-2025-38465: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: netlink: Fix wraparounds of sk->sk_rmem_alloc. Netlink has this pattern in some places if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) atomic_add(skb->truesize, &sk->sk_rmem_alloc); , which has the same problem fixed by commit 5a465a0da13e ("udp: Fix multiple wraparounds of sk->sk_rmem_alloc."). For example, if we set INT_MAX to SO_RCVBUFFORCE, the condition is always false as the two operands are of int. Then, a single socket can eat as many skb as possible until OOM happens, and we can see multiple wraparounds of sk->sk_rmem_alloc. Let's fix it by using atomic_add_return() and comparing the two variables as unsigned int. Before: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port -1668710080 0 rtnl:nl_wraparound/293 * After: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port 2147483072 0 rtnl:nl_wraparound/290 * ^ `--- INT_MAX - 576

Affected products

  • Debian Debian Linux: version 11.0 only
  • Linux Linux Kernel: from 2.6.13, before 5.4.296 (fixed in 5.4.296); from 5.5, before 5.10.240 (fixed in 5.10.240); from 5.11, before 5.15.189 (fixed in 5.15.189); from 5.16, before 6.1.146 (fixed in 6.1.146); from 6.2, before 6.6.99 (fixed in 6.6.99); from 6.7, before 6.12.39 (fixed in 6.12.39); …

Published 2025-07-25. Last modified 2026-06-17.