Bug 2436810 (CVE-2026-23098)

Summary: CVE-2026-23098 kernel: netrom: fix double-free in nr_route_frame()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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OS: Linux   
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Description OSIDB Bzimport 2026-02-04 17:04:29 UTC 
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.
Comment 1 Jon Moroney 2026-02-04 20:50:46 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026020427-CVE-2026-23098-1fd2@gregkh/T