{"id":"CVE-2026-89700","title":"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","summary":"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_NE…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:H","cwe":["CWE-125"],"vendor":"Linux","product":"Linux","affected":["Linux >= 16a471177496c8e04a9793812c187a2c1a2192fa < bf85a0f1e45258f90ceeec14772b5769697dfd75","Linux >= 16a471177496c8e04a9793812c187a2c1a2192fa < 2aca70c18c5f5d06004122861fb151d5fcc57faf","Linux >= 16a471177496c8e04a9793812c187a2c1a2192fa < 22d0e4752ca88fd84196d22ebeedc905e6540440","Linux >= 16a471177496c8e04a9793812c187a2c1a2192fa < bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464","Linux 6.10"],"published":"2026-09-11","updated":"2026-09-21","sourceUpdated":"2026-09-21T14:17:25.580","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89700","references":[{"url":"https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bf85a0f1e45258f90ceeec14772b5769697dfd75","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89700.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89700"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532454"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89700"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89700"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89700.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00166,"epssPercentile":0.06246,"cvssSource":"vendor","ingestedAt":"2026-09-14T11:11:19.885Z","slug":"CVE-2026-89700","body":"## Overview\n\nIn 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89700.json)","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":203972,"id":"CVE-2026-89700","ts":1789490230860,"field":"cvss","old":null,"new":"4.7"},{"seq":203971,"id":"CVE-2026-89700","ts":1789490230860,"field":"severity","old":"none","new":"medium"},{"seq":147191,"id":"CVE-2026-89700","ts":1789270200107,"field":"cvss","old":null,"new":"4.7"},{"seq":147190,"id":"CVE-2026-89700","ts":1789270200107,"field":"severity","old":"none","new":"medium"},{"seq":108946,"id":"CVE-2026-89700","ts":1789183729674,"field":"cvss","old":null,"new":"4.7"},{"seq":108945,"id":"CVE-2026-89700","ts":1789183729674,"field":"severity","old":"none","new":"medium"}]}