CVE Catalog

CVE-2026-98102

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel, a bug in ip6_mc_del1_src() related to RCU lists in IPv6 multicast was fixed. Previously, when a source filter was removed, the pointer was mutated before the grace period, which could cause concurrent readers to see the tombstone list instead of the proper source list.

Risk Assessment

The vulnerability could cause incorrect IPv6 multicast behavior, including missing active sources or examining deleted entries, potentially disrupting applications using multicast.

Recommendation

Update the Linux kernel to a version containing the fix. Test IPv6 multicast applications after the update.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: fix RCU list diversion in ip6_mc_del1_src() When removing a source filter whose count reaches zero, ip6_mc_del1_src() unlinks psf from pmc->mca_sources. If the filter was previously active, the code moved psf directly into pmc->mca_tomb by updating psf->sf_next. Because pmc->mca_sources is traversed locklessly under RCU (e.g. by ipv6_chk_mcast_addr()), mutating psf->sf_next before a grace period elapses diverts concurrent readers to the tombstone list. Consequently, readers miss remaining active sources in pmc->mca_sources and improperly examine deleted tombstone entries. Fix this by allocating a new tombstone node for pmc->mca_tomb (as done in sf_setstate()) and retiring the original psf via kfree_rcu().

Vulnerability data from NVD (NIST) · CISA KEV · EPSS