{"id":"CVE-2026-89700","state":"PUBLISHED","title":"nfsd: validate sockaddr length per family in listener_set","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: validate sockaddr length per family in listener_set\n\nnfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY\nattribute with no minimum length. A CAP_NET_ADMIN caller can send a\n16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte\nOOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,\nkernel_bind).\n\nnfsd_nl_listener_set_doit() also parsed and validated each listener\nentry inline in two separate loops, interleaved with mutating the\nrunning listener configuration. The validation was duplicated, used an\nopen-coded \"nla_len < sizeof(struct sockaddr)\" check that was too short\nfor AF_INET6, and handled a malformed entry inconsistently depending on\nwhich loop noticed it.\n\nAdd an nfsd_nl_validate_listeners() helper that walks the entire list\nonce and confirms each entry parses, carries both an address and a\ntransport name, and is long enough for its address family\n(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)\nfor AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking\nnfsd_mutex or creating the serv, so a malformed request fails cleanly\nwith no side effects.\n\nSince every entry is known valid by the time the two existing loops\nrun, drop the redundant presence and per-family length checks from\nboth, leaving only the nla_parse_nested() call needed to extract the\ndata.","publishedAt":"2026-09-11T19:46:18.076Z","updatedAt":"2026-10-19T08:51:13.379Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"bf85a0f1e45258f90ceeec14772b5769697dfd75","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"2aca70c18c5f5d06004122861fb151d5fcc57faf","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"22d0e4752ca88fd84196d22ebeedc905e6540440","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfsctl.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","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":["fs/nfsd/nfsctl.c"]}],"references":["https://git.kernel.org/stable/c/bf85a0f1e45258f90ceeec14772b5769697dfd75","https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf","https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440","https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89700.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89700","state":"PUBLISHED","datePublished":"2026-09-11T19:46:18.076Z","dateUpdated":"2026-10-19T08:51:13.379Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.750Z"},"containers":{"cna":{"title":"nfsd: validate sockaddr length per family in listener_set","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: validate sockaddr length per family in listener_set\n\nnfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY\nattribute with no minimum length. A CAP_NET_ADMIN caller can send a\n16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte\nOOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,\nkernel_bind).\n\nnfsd_nl_listener_set_doit() also parsed and validated each listener\nentry inline in two separate loops, interleaved with mutating the\nrunning listener configuration. The validation was duplicated, used an\nopen-coded \"nla_len < sizeof(struct sockaddr)\" check that was too short\nfor AF_INET6, and handled a malformed entry inconsistently depending on\nwhich loop noticed it.\n\nAdd an nfsd_nl_validate_listeners() helper that walks the entire list\nonce and confirms each entry parses, carries both an address and a\ntransport name, and is long enough for its address family\n(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)\nfor AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking\nnfsd_mutex or creating the serv, so a malformed request fails cleanly\nwith no side effects.\n\nSince every entry is known valid by the time the two existing loops\nrun, drop the redundant presence and per-family length checks from\nboth, leaving only the nla_parse_nested() call needed to extract the\ndata."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"bf85a0f1e45258f90ceeec14772b5769697dfd75","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"2aca70c18c5f5d06004122861fb151d5fcc57faf","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"22d0e4752ca88fd84196d22ebeedc905e6540440","versionType":"git"},{"version":"16a471177496c8e04a9793812c187a2c1a2192fa","status":"affected","lessThan":"bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfsctl.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","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":["fs/nfsd/nfsctl.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/bf85a0f1e45258f90ceeec14772b5769697dfd75"},{"url":"https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf"},{"url":"https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440"},{"url":"https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:51:13.379Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}