{"id":"CVE-2026-98102","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: fix RCU list diversion in ip6_mc_del1_src()\n\nWhen removing a source filter whose count reaches zero, ip6_mc_del1_src()\nunlinks psf from pmc->mca_sources","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: fix RCU list diversion in ip6_mc_del1_src()\n\nWhen removing a source filter whose count reaches zero, ip6_mc_del1_src()\nunlinks psf from pmc->mca_sources. I…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4b200e398953c237c86d32bf26d4cb2a96556a6f < 4352737297b262e8367675c19a7dc6a9f53c97af","Linux >= 4b200e398953c237c86d32bf26d4cb2a96556a6f < 8d4fe5c13f5056faa6deb09a90e24a89f9ebfad4","Linux >= 4b200e398953c237c86d32bf26d4cb2a96556a6f < 5149c60c406595b56fda0c6e9aae7fd287f636aa","Linux >= 4b200e398953c237c86d32bf26d4cb2a96556a6f < 93b49239840b91313adbd77b8b52993eff2d08c1","Linux 86c49119f0353f857cc08030ec9e4ebaab3d5a64","Linux >= 5.10.261 < 5.11","Linux 5.13"],"published":"2026-09-25","updated":"2026-09-25","sourceUpdated":"2026-09-25T11:17:39.943","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98102","references":[{"url":"https://git.kernel.org/stable/c/4352737297b262e8367675c19a7dc6a9f53c97af","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5149c60c406595b56fda0c6e9aae7fd287f636aa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8d4fe5c13f5056faa6deb09a90e24a89f9ebfad4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/93b49239840b91313adbd77b8b52993eff2d08c1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-25T11:06:38.826Z","slug":"CVE-2026-98102","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: fix RCU list diversion in ip6_mc_del1_src()\n\nWhen removing a source filter whose count reaches zero, ip6_mc_del1_src()\nunlinks psf from pmc->mca_sources. If the filter was previously active,\nthe code moved psf directly into pmc->mca_tomb by updating psf->sf_next.\n\nBecause pmc->mca_sources is traversed locklessly under RCU (e.g. by\nipv6_chk_mcast_addr()), mutating psf->sf_next before a grace period\nelapses diverts concurrent readers to the tombstone list. Consequently,\nreaders miss remaining active sources in pmc->mca_sources and improperly\nexamine deleted tombstone entries.\n\nFix this by allocating a new tombstone node for pmc->mca_tomb (as done\nin sf_setstate()) and retiring the original psf via kfree_rcu().\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}