{"id":"CVE-2026-99071","state":"PUBLISHED","title":"ipv4: do not warn on route notification size race","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: do not warn on route notification size race\n\nCommit 680aea08e78c (\"net: ipv4: Emit notification when fib hardware\nflags are changed\") added asynchronous route notifications for hardware\nflag changes.\n\nfib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later\nfills it with fib_dump_info() while holding only RCU.  With nexthop\ncompatibility mode enabled, a concurrent replacement can grow the group\nbetween these independent snapshots.  fib_dump_info() can then\nlegitimately return -EMSGSIZE, so the warning does not prove a sizing bug.\n\nRemove the warning.  The existing error path still frees the skb and\nreports the error to listeners.","publishedAt":"2026-10-23T12:23:14.297Z","updatedAt":"2026-10-30T12:41:30.940Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"8b35e7767fdee63e57948a1ec89d9238a651f8c6","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"096ad0cb77f8da1928d04a0d170535e14ca6311b","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"088ba80eef85fa7a5ad8f9e7c82b403c99242b56","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"78a1cf5c54b2f795c81fedb530755a8d01cc84f0","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"7dfa7ca97f3ac46353edd4cc44f7733758e4535b","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"221ef5e1e44a044790f0f54e6aa237883f475a4d","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"e02a5b6588161673ef75a4bc5cdfb62bd493374d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/fib_trie.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","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/ipv4/fib_trie.c"]}],"references":["https://git.kernel.org/stable/c/8b35e7767fdee63e57948a1ec89d9238a651f8c6","https://git.kernel.org/stable/c/096ad0cb77f8da1928d04a0d170535e14ca6311b","https://git.kernel.org/stable/c/088ba80eef85fa7a5ad8f9e7c82b403c99242b56","https://git.kernel.org/stable/c/78a1cf5c54b2f795c81fedb530755a8d01cc84f0","https://git.kernel.org/stable/c/7dfa7ca97f3ac46353edd4cc44f7733758e4535b","https://git.kernel.org/stable/c/221ef5e1e44a044790f0f54e6aa237883f475a4d","https://git.kernel.org/stable/c/e02a5b6588161673ef75a4bc5cdfb62bd493374d"],"weaknesses":[],"ingestedAt":"2026-10-30T13:02:04.640Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/99xxx/CVE-2026-99071.json","commit":"cb14bf1b43b0c9f05f7f40eae2246263fd430780","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99071","state":"PUBLISHED","datePublished":"2026-10-23T12:23:14.297Z","dateUpdated":"2026-10-30T12:41:30.940Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.389Z"},"containers":{"cna":{"title":"ipv4: do not warn on route notification size race","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: do not warn on route notification size race\n\nCommit 680aea08e78c (\"net: ipv4: Emit notification when fib hardware\nflags are changed\") added asynchronous route notifications for hardware\nflag changes.\n\nfib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later\nfills it with fib_dump_info() while holding only RCU.  With nexthop\ncompatibility mode enabled, a concurrent replacement can grow the group\nbetween these independent snapshots.  fib_dump_info() can then\nlegitimately return -EMSGSIZE, so the warning does not prove a sizing bug.\n\nRemove the warning.  The existing error path still frees the skb and\nreports the error to listeners."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"8b35e7767fdee63e57948a1ec89d9238a651f8c6","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"096ad0cb77f8da1928d04a0d170535e14ca6311b","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"088ba80eef85fa7a5ad8f9e7c82b403c99242b56","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"78a1cf5c54b2f795c81fedb530755a8d01cc84f0","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"7dfa7ca97f3ac46353edd4cc44f7733758e4535b","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"221ef5e1e44a044790f0f54e6aa237883f475a4d","versionType":"git"},{"version":"680aea08e78c003292415518ad270bc20f9c80b1","status":"affected","lessThan":"e02a5b6588161673ef75a4bc5cdfb62bd493374d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/fib_trie.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","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/ipv4/fib_trie.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/8b35e7767fdee63e57948a1ec89d9238a651f8c6"},{"url":"https://git.kernel.org/stable/c/096ad0cb77f8da1928d04a0d170535e14ca6311b"},{"url":"https://git.kernel.org/stable/c/088ba80eef85fa7a5ad8f9e7c82b403c99242b56"},{"url":"https://git.kernel.org/stable/c/78a1cf5c54b2f795c81fedb530755a8d01cc84f0"},{"url":"https://git.kernel.org/stable/c/7dfa7ca97f3ac46353edd4cc44f7733758e4535b"},{"url":"https://git.kernel.org/stable/c/221ef5e1e44a044790f0f54e6aa237883f475a4d"},{"url":"https://git.kernel.org/stable/c/e02a5b6588161673ef75a4bc5cdfb62bd493374d"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:41:30.940Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.12.113"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"7.2.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}