Description
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: Avoid nf_ct_helper_hash uses after free
If nf_conntrack_init_start() fails (for example due to a register_nf_conntrack_bpf() failure), the nf_conntrack_helper_fini() clean-up path frees the nf_ct_helper_hash map.
When built with NF_CONNTRACK=y, further netfilter modules (e.g: netfilter_conntrack_ftp) can still be loaded and call nf_conntrack_helpers_register(), independently of whether nf_conntrack initialized correctly. This accesses the nf_ct_helper_hash dangling pointer and causes a uaf, possibly leading to random memory corruption.
This patch guards nf_conntrack_helper_register() from accessing a freed or uninitialized nf_ct_helper_hash pointer and fixes possible uses-after-free when loading a conntrack module.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 4ee69c91cb8f9ca144bc0861969e5a1a3c6152a7; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 00716f25f9697d02a0d9bd622575c7c7321ba3d0; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 61c7a5256543ae7d24cd9d21853d514c8632e1e9; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 8289d422f5e484efe4a565fe18e862ecd621c175; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 6f03ce2f1abcb9f9d0511e3659ca6eb60e39f566; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 05561f822f27b9fa88fa5504ddec34bf38833034; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < fce5cc7cbd4b92f979bf02c9ec5fb69aaeba92d7; >= 12f7a505331e6b2754684b509f2ac8f0011ce644, < 6eef7a2b933885a17679eb8ed0796ddf0ee5309b |
| Linux | Linux | 3.6 |
References
- https://git.kernel.org/stable/c/00716f25f9697d02a0d9bd622575c7c7321ba3d0Patch
- https://git.kernel.org/stable/c/05561f822f27b9fa88fa5504ddec34bf38833034Patch
- https://git.kernel.org/stable/c/4ee69c91cb8f9ca144bc0861969e5a1a3c6152a7Patch
- https://git.kernel.org/stable/c/61c7a5256543ae7d24cd9d21853d514c8632e1e9Patch
- https://git.kernel.org/stable/c/6eef7a2b933885a17679eb8ed0796ddf0ee5309bPatch
- https://git.kernel.org/stable/c/6f03ce2f1abcb9f9d0511e3659ca6eb60e39f566Patch
- https://git.kernel.org/stable/c/8289d422f5e484efe4a565fe18e862ecd621c175Patch
- https://git.kernel.org/stable/c/fce5cc7cbd4b92f979bf02c9ec5fb69aaeba92d7Patch
Timeline
- Published
- Oct 7, 2025
- Last modified
- Oct 15, 2026
- NVD status
- Modified