Description
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix use-after-free in ip6_finish_output2()
ip6_finish_output2() caches a pointer to the IPv6 destination address (daddr) before invoking lwtunnel_xmit(). The LWT-BPF transmit path or other encapsulation operations within lwtunnel_xmit() can reallocate the skb head, freeing the memory that daddr points to. When lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, the function continues to use the stale daddr pointer to compute the nexthop and to look up or create the neighbour entry. This results in a use-after-free read, which can leak sensitive kernel data, pollute the neighbour table with arbitrary values, misdirect traffic, or crash the system.
Fix this by re-fetching the IPv6 header and the destination address pointer after lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop computation and neighbour lookup operate on valid memory.
Metrics
No CVSS score has been published yet.
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 4132c4ad00ddbf3a175ea0d2c775b662a32f4c85, < 75e0a544ebe9af663ef53ca21e9e9185c51fb54a; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < c95f01b78266828a57060d754fcbfc92123a98ed; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < d960881b9312e781a3429aabceb223ce6b7c882f; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < 087ee0d914aaae929f1660c9ca878e367655ba1a; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < 3c770ac4e6f07af7c7b40c474a3efc61ffed7862; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < 3dc98e5fe82d069dd29b124ffbdb679331dfea43; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < 99219c82804f266189388e8bf1cf5135d10d5515; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < 73a187384a8c8b983c7fea046d716b6752a1e7a3; >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2, < d0d48d999b0eee6bb176ef4e39d9be868fa80f7e; 1598154fd28ffa4a55beae1970475fd6776554b6; >= 5.10.233, < 5.10.267; >= 5.4.289, < 5.5 |
| Linux | Linux | 5.15 |
References
- https://git.kernel.org/stable/c/087ee0d914aaae929f1660c9ca878e367655ba1a
- https://git.kernel.org/stable/c/3c770ac4e6f07af7c7b40c474a3efc61ffed7862
- https://git.kernel.org/stable/c/3dc98e5fe82d069dd29b124ffbdb679331dfea43
- https://git.kernel.org/stable/c/73a187384a8c8b983c7fea046d716b6752a1e7a3
- https://git.kernel.org/stable/c/75e0a544ebe9af663ef53ca21e9e9185c51fb54a
- https://git.kernel.org/stable/c/99219c82804f266189388e8bf1cf5135d10d5515
- https://git.kernel.org/stable/c/c95f01b78266828a57060d754fcbfc92123a98ed
- https://git.kernel.org/stable/c/d0d48d999b0eee6bb176ef4e39d9be868fa80f7e
- https://git.kernel.org/stable/c/d960881b9312e781a3429aabceb223ce6b7c882f
Timeline
- Published
- Sep 4, 2026
- Last modified
- Nov 6, 2026
- NVD status
- Received