CVE-2025-21719

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to the version that includes the fix for the issue described

Description A vulnerability in the Linux kernel has been identified, where calling mr mfc uses dev() for unres entries would cause a crash due to aliasing of c->mfc un.res.minvif and c->mfc un.res.maxvif to "struct sk buff head unresolved", which contains two pointers. This issue was found by syzbot and is related to the ipmr module. The crash occurs because of a wild-memory-access in a specific range.

Recommendations For Linux kernel versions prior to the fixed version, consider applying the patch that removes the problematic code to resolve the issue. As a temporary workaround, consider disabling the mr mfc uses dev() function until a patch is available.