CVE-2023-53559: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ip_vti: fix potential slab-use-after-free in decode_session6 When ip_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ip_vti device sends IPv6 packets. As commit f855691975bb ("xfrm6: Fix the nexthdr offset in _decode_session6.") showed, xfrm_decode_session was originally intended only for the receive path. IP6CB(skb)->nhoff is not set during transmission. Therefore, set the cb field in the skb to 0 before sending packets.

Affected products

• Linux Linux Kernel: from 3.19.1, before 4.14.324 (fixed in 4.14.324); from 4.15, before 4.19.293 (fixed in 4.19.293); from 4.20, before 5.4.255 (fixed in 5.4.255); from 5.5, before 5.10.192 (fixed in 5.10.192); from 5.11, before 5.15.128 (fixed in 5.15.128); from 5.16, before 6.1.47 (fixed in 6.1.47); …

Published 2025-10-04. Last modified 2026-08-04.