{"id":"CVE-2026-99031","state":"PUBLISHED","title":"net: bridge: avoid recursive multicast port cleanup","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: avoid recursive multicast port cleanup\n\nbr_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL\nport groups by calling br_multicast_del_pg(). For S,G entries, that\ndeletion calls back into br_multicast_sg_del_exclude_ports(), so a large\nnumber of STAR_EXCL ports consumes one kernel stack frame per port and can\nhit the stack guard page.\n\nKeep the complete port-group deletion path for cleanup, but suppress the\nS,G exclude-port cleanup while that helper is already walking the same\nentry. Normal deletion callers retain the existing behavior.","publishedAt":"2026-10-23T12:21:31.535Z","updatedAt":"2026-10-30T12:41:04.054Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"0ed8edcbcf2290dba13c1beeba27fc19ad38515b","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"6a7385f6605958aa69eeb185c91f45d77640d1e2","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"26142868b0767e95e28b7a1237f58b292b54d1d9","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"2fb87c6025f90191516bee3ce14b42eb3e1cfed7","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"d109141ba14652146089ef78b32d5e4d5285ebad","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"7931fb9181421953f3133b408b0f2e2b8dd68b61","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"5158353121bae4f552cb677ce8c5c3ef52f93a0d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bridge/br_multicast.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.113","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bridge/br_multicast.c"]}],"references":["https://git.kernel.org/stable/c/0ed8edcbcf2290dba13c1beeba27fc19ad38515b","https://git.kernel.org/stable/c/6a7385f6605958aa69eeb185c91f45d77640d1e2","https://git.kernel.org/stable/c/26142868b0767e95e28b7a1237f58b292b54d1d9","https://git.kernel.org/stable/c/695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64","https://git.kernel.org/stable/c/2fb87c6025f90191516bee3ce14b42eb3e1cfed7","https://git.kernel.org/stable/c/d109141ba14652146089ef78b32d5e4d5285ebad","https://git.kernel.org/stable/c/7931fb9181421953f3133b408b0f2e2b8dd68b61","https://git.kernel.org/stable/c/5158353121bae4f552cb677ce8c5c3ef52f93a0d"],"weaknesses":[],"ingestedAt":"2026-10-30T13:00:06.648Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/99xxx/CVE-2026-99031.json","commit":"cb14bf1b43b0c9f05f7f40eae2246263fd430780","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99031","state":"PUBLISHED","datePublished":"2026-10-23T12:21:31.535Z","dateUpdated":"2026-10-30T12:41:04.054Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.387Z"},"containers":{"cna":{"title":"net: bridge: avoid recursive multicast port cleanup","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: avoid recursive multicast port cleanup\n\nbr_multicast_sg_del_exclude_ports() removes automatically added STAR_EXCL\nport groups by calling br_multicast_del_pg(). For S,G entries, that\ndeletion calls back into br_multicast_sg_del_exclude_ports(), so a large\nnumber of STAR_EXCL ports consumes one kernel stack frame per port and can\nhit the stack guard page.\n\nKeep the complete port-group deletion path for cleanup, but suppress the\nS,G exclude-port cleanup while that helper is already walking the same\nentry. Normal deletion callers retain the existing behavior."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"0ed8edcbcf2290dba13c1beeba27fc19ad38515b","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"6a7385f6605958aa69eeb185c91f45d77640d1e2","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"26142868b0767e95e28b7a1237f58b292b54d1d9","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"2fb87c6025f90191516bee3ce14b42eb3e1cfed7","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"d109141ba14652146089ef78b32d5e4d5285ebad","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"7931fb9181421953f3133b408b0f2e2b8dd68b61","versionType":"git"},{"version":"8266a0491e92d39dc9af739e8380a0daa9b8836b","status":"affected","lessThan":"5158353121bae4f552cb677ce8c5c3ef52f93a0d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bridge/br_multicast.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.113","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bridge/br_multicast.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/0ed8edcbcf2290dba13c1beeba27fc19ad38515b"},{"url":"https://git.kernel.org/stable/c/6a7385f6605958aa69eeb185c91f45d77640d1e2"},{"url":"https://git.kernel.org/stable/c/26142868b0767e95e28b7a1237f58b292b54d1d9"},{"url":"https://git.kernel.org/stable/c/695a5a4c69c922d9296b2d7ad5f1ce8c6858fc64"},{"url":"https://git.kernel.org/stable/c/2fb87c6025f90191516bee3ce14b42eb3e1cfed7"},{"url":"https://git.kernel.org/stable/c/d109141ba14652146089ef78b32d5e4d5285ebad"},{"url":"https://git.kernel.org/stable/c/7931fb9181421953f3133b408b0f2e2b8dd68b61"},{"url":"https://git.kernel.org/stable/c/5158353121bae4f552cb677ce8c5c3ef52f93a0d"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:41:04.054Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.12.113"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"7.2.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}