netrom: fix double-free in nr_route_frame()
In the Linux kernel, the following vulnerability has been resolved: netrom: fix double-free in nr_route_frame() In nr_route_frame(), old_skb is immediately freed without checking if nr_neigh->ax25 pointer is NULL. Therefore, if nr_neigh->ax25 is NULL, the caller function will free old_skb again, causing a double-free bug. Therefore, to prevent this, we need to modify it to check whether nr_neigh->ax25 is NULL before freeing old_skb.
02 / AFFECTED SOFTWARE
Affected packages
1698 explicit affected versions
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: netrom: fix double-free in nr_route_frame() In nr_route_frame(), old_skb is immediately freed without checking if nr_neigh->ax25 pointer is NULL. Therefore, if nr_neigh->ax25 is NULL, the caller function will free old_skb again, causing a double-free bug. Therefore, to prevent this, we need to modify it to check whether nr_neigh->ax25 is NULL before freeing old_skb.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/25aab6bfc31017a7e52035b99aef5c2b6bde8ffb
- https://git.kernel.org/stable/c/6e0110ea90313b7c0558a0b77038274a6821caf8
- https://git.kernel.org/stable/c/7c48fdf2d1349bb54815b56fb012b9d577707708
- https://git.kernel.org/stable/c/94d1a8bd08af1f4cc345c5c29f5db1ea72b8bb8c
- https://git.kernel.org/stable/c/9f5fa78d9980fe75a69835521627ab7943cb3d67
- https://git.kernel.org/stable/c/ba1096c315283ee3292765f6aea4cca15816c4f7
- https://git.kernel.org/stable/c/bd8955337e3764f912f49b360e176d8aaecf7016
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23098.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-23098