CVE-2022-48809: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.3% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net: fix a memleak when uncloning an skb dst and its metadata When uncloning an skb dst and its associated metadata, a new dst+metadata is allocated and later replaces the old one in the skb. This is helpful to have a non-shared dst+metadata attached to a specific skb. The issue is the uncloned dst+metadata is initialized with a refcount of 1, which is increased to 2 before attaching it to the skb. When tun_dst_unclone returns, the dst+metadata is only referenced from a single place (the skb) while its refcount is 2. Its refcount will never drop to 0 (when the skb is consumed), leading to a memory leak. Fix this by removing the call to dst_hold in tun_dst_unclone, as the dst+metadata refcount is already 1.

Affected products

• Linux Linux Kernel: from 4.3, before 4.9.302 (fixed in 4.9.302); from 4.10, before 4.14.267 (fixed in 4.14.267); from 4.15, before 4.19.230 (fixed in 4.19.230); from 4.20, before 5.4.180 (fixed in 5.4.180); from 5.5, before 5.10.101 (fixed in 5.10.101); from 5.11, before 5.15.24 (fixed in 5.15.24); …

Published 2024-07-16. Last modified 2026-06-17.