{"id":"CVE-2026-64422","revision":null,"records":[{"revision":"741e5dfae8c24c98b6513cc1cedc9757","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-64422","aliases":[],"title":"net: ipv4: bound TCP reordering sysctl writes and MTU probe sizes","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv4: bound TCP reordering sysctl writes and MTU probe sizes\n\nReject invalid `net.ipv4.tcp_reordering` values before they reach TCP\nsocket state. The sysctl is stored as an `int` but copied into the\n`u32` `tp->reordering` field for new sockets, so negative writes wrap\nto large values.\n\nWith `tcp_mtu_probing=2`, the wrapped value can overflow the\n`tcp_mtu_probe()` size calculation and drive the MTU probing path into\nan out-of-bounds read. Route `tcp_reordering` writes through\n`proc_dointvec_minmax()` and require it to be at least 1. Also require\n`tcp_max_reordering` to be at least 1 so the configured maximum cannot\nbecome negative either.\n\nWhen registering the table for a non-init network namespace, relocate\n`extra2` pointers that refer into `init_net.ipv4` so the\n`tcp_reordering` upper bound follows that namespace's\n`tcp_max_reordering`.\n\nHarden `tcp_mtu_probe()` itself by computing `size_needed` as `u64`.\nThis keeps the send queue and window checks from being bypassed through\nsigned integer overflow.","state":0,"publishedAt":"2026-07-25T08:51:00.671+00:00","modifiedAt":"2026-10-19T20:38:28.132+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/ipv4/sysctl_net_ipv4.c\",\n \"net/ipv4/tcp_output.c\"\n ],\n \"versions\": [\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"f0d88a4cd03affff6c08adf6c63964e235aede43\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"27ddf4486c7dbf5bdd393fa8bef6b67179796d98\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"782708ca1ea1f68b8cbb5ea3a7f5f18d0000efae\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"e81f805824a8109504fce090641b17d135b48cd1\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"99206ce2244f8a3ed64298d0667c9055845a5dc7\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"bbae351c0f32f7c200249e4aa6561b2b419dcf69\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"a094ac95d3b69adfa1676eb9c8eae6835d4f1671\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"91cc17c0e5e5ada156a8d5787a2509d263ea6bbf\",\n \"lessThan\": \"efb8763d7bbb40cff4cc55a6b62c3095a038149c\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"net/ipv4/sysctl_net_ipv4.c\",\n \"net/ipv4/tcp_output.c\"\n ],\n \"versions\": [\n {\n \"version\": \"2.6.24\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"2.6.24\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.261\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.212\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.178\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.145\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.96\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.39\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.1.4\",\n \"lessThanOrEqual\": \"7.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/f0d88a4cd03affff6c08adf6c63964e235aede43","https://git.kernel.org/stable/c/27ddf4486c7dbf5bdd393fa8bef6b67179796d98","https://git.kernel.org/stable/c/782708ca1ea1f68b8cbb5ea3a7f5f18d0000efae","https://git.kernel.org/stable/c/e81f805824a8109504fce090641b17d135b48cd1","https://git.kernel.org/stable/c/99206ce2244f8a3ed64298d0667c9055845a5dc7","https://git.kernel.org/stable/c/bbae351c0f32f7c200249e4aa6561b2b419dcf69","https://git.kernel.org/stable/c/a094ac95d3b69adfa1676eb9c8eae6835d4f1671","https://git.kernel.org/stable/c/efb8763d7bbb40cff4cc55a6b62c3095a038149c"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-64422","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-64422","identifiers":["CVE-2026-64422"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-08T16:11:32.8669692+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-08T16:11:32.8669692+00:00","lastSuccessAt":"2026-11-08T16:11:33.0663673+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:33.0663692+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-eaa64dac63caa79c8d4905619258c41c51b39e461b996124e1a21b5e85e7e738-8efc3185ca756d5b7422ffb0b03b28efb013f2613f9dfca00a2fb41576507917","complete":true,"records":421174,"lastAttemptAt":"2026-11-08T16:11:31.8941159+00:00","lastSuccessAt":"2026-11-08T16:11:31.6860236+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:31.8941159+00:00","snapshotPublishedAt":"2026-11-08T15:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-3c4bbd4ca5ed46108ac75e394fa48ace","complete":true,"records":13654,"lastAttemptAt":"2026-11-08T16:11:35.9510843+00:00","lastSuccessAt":"2026-11-08T16:11:35.947+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:35.947+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13706,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-08T16:11:32.8669692+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-08T16:11:32.8669692+00:00","lastSuccessAt":"2026-11-08T16:11:33.0716184+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:33.0716198+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-7f3b9e580ebe475bb44f224af7ef38ba","complete":true,"records":13666,"lastAttemptAt":"2026-11-08T16:11:35.0811636+00:00","lastSuccessAt":"2026-11-08T16:11:35.077+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:35.077+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13706,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-980593e6977a6d1b4fb1eed5a1ffe88a468736f89f0a06f710924ad59132c023","complete":true,"records":9914,"lastAttemptAt":"2026-11-08T16:11:32.7092062+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:32.7092062+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-08T16:11:32.0361288+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:32.0361288+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-964c14035e6f0f6478b2870fad6a7ef9f6045876d4a12af2c2e514521e54b6af","complete":true,"records":3055,"lastAttemptAt":"2026-11-08T16:11:32.8190262+00:00","lastSuccessAt":"2026-11-08T11:07:12.1927025+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:32.8190262+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-f8647d7ba64b1ba0dfdc7130944766d5b36d5b77d18fff0c79e651a4cff3c2b9","complete":true,"records":231293,"lastAttemptAt":"2026-11-08T16:11:32.2222906+00:00","lastSuccessAt":"2026-11-08T11:06:56.2918717+00:00","error":null,"lastVerifiedAt":"2026-11-08T16:11:32.2222906+00:00","snapshotPublishedAt":"2026-11-08T11:02:50+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}