{"id":"CVE-2026-89674","revision":null,"records":[{"revision":"4b597f4fc58944ff9014fc9369cfd9b0","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89674","aliases":[],"title":"nfsd: fix XDR length calculation in nfsd4_ff_encode_layoutget","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix XDR length calculation in nfsd4_ff_encode_layoutget\n\nThe XDR buffer size calculation in nfsd4_ff_encode_layoutget() has\nmultiple errors that can result in either an out-of-bounds write or\nleaking uninitialized kernel memory to the client:\n\n - fh_len doesn't account for XDR padding on the file handle data\n - uid and gid lengths use \"8 + len\" but xdr_encode_opaque() actually\n   writes \"4 + xdr_align_size(len)\" bytes\n - ds_len omits the flags and stats_collect_hint fields (8 bytes),\n   while len's header constant overestimates by 8 bytes -- these\n   partially cancel but leave a net mismatch\n\nThe worst case occurs with short strings (e.g. uid=0, gid=0 with an\nodd-sized file handle), where the function writes up to 5 bytes past\nthe reserved XDR buffer. Conversely, when string lengths happen to be\n4-byte aligned, the reservation is too large and stale buffer content\nis sent to the client.\n\nFix this by breaking out every encoded field explicitly in the ds_len\ncalculation, using xdr_align_size() for all variable-length opaque\nfields, and correcting the header constants.","state":0,"publishedAt":"2026-09-11T19:45:58.883+00:00","modifiedAt":"2026-10-19T08:50:47.609+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                        \"fs/nfsd/flexfilelayoutxdr.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"3a7fd224df0fbb42167eb1b77be45d72fe0b1098\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"29e4478e2ed5a227e8f0c33cacb91bf227cedd47\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"65a72b721943618eeb3a41c8b36e915591f3f83f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"bee826c00ac900473f91306f1f3e5a5a81fd4a74\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"e7d9d23ecd9172f05b09bb678ff22db8e361c428\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"0380129b1373c437eb35401a174671c8888f4b80\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"c81cef6a805dec266c10fc4f83c93d6fcf1a2b43\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"9b9960a0ca4773e21c4b153ed355583946346b25\",\n                            \"lessThan\": \"f9868174af49d207fbaf0c5e055d088a983684af\",\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                        \"fs/nfsd/flexfilelayoutxdr.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.8\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.8\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.270\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.221\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.188\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.157\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.109\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.50\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.4\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/3a7fd224df0fbb42167eb1b77be45d72fe0b1098","https://git.kernel.org/stable/c/29e4478e2ed5a227e8f0c33cacb91bf227cedd47","https://git.kernel.org/stable/c/65a72b721943618eeb3a41c8b36e915591f3f83f","https://git.kernel.org/stable/c/bee826c00ac900473f91306f1f3e5a5a81fd4a74","https://git.kernel.org/stable/c/e7d9d23ecd9172f05b09bb678ff22db8e361c428","https://git.kernel.org/stable/c/0380129b1373c437eb35401a174671c8888f4b80","https://git.kernel.org/stable/c/c81cef6a805dec266c10fc4f83c93d6fcf1a2b43","https://git.kernel.org/stable/c/f9868174af49d207fbaf0c5e055d088a983684af"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89674","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89674","identifiers":["CVE-2026-89674"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. 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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-0e1130a95bab4b43bc10624fd5ee853a","complete":false,"records":13654,"lastAttemptAt":"2026-11-09T04:16:03.8367163+00:00","lastSuccessAt":"2026-11-09T04:16:03.832+00:00","error":"8 identifier lookups failed; latest failures include HTTP 403. Other identifiers were checked independently.","lastVerifiedAt":"2026-11-09T04:16:03.832+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13653,"expectedIdentifiers":13706,"failedIdentifiers":8},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-09T04:03:51.7811525+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-09T04:03:51.7811525+00:00","lastSuccessAt":"2026-11-09T04:03:51.948408+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.9484081+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-5a44a451442747cb81d83104fe1e7771","complete":true,"records":13666,"lastAttemptAt":"2026-11-09T04:03:52.3882913+00:00","lastSuccessAt":"2026-11-09T02:08:52.274+00:00","error":null,"lastVerifiedAt":"2026-11-09T02:08:52.274+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":"2026-11-09T04:03:51.3592849+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.3592849+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":"2026-11-09T04:02:14.6671491+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:02:14.6671491+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-3b1150af6d7ada2c07356cbab4ead5224c1485027890f71c71d0742cddf0b9e8","complete":true,"records":3055,"lastAttemptAt":"2026-11-09T04:03:51.7519249+00:00","lastSuccessAt":"2026-11-09T00:02:23.4330288+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.7519249+00:00","snapshotPublishedAt":"2026-11-08T23:17:54+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-6a1c845b1938b1aa788f0e95c9ac8a8d5a1f07caed5d155840b0616b548c1455","complete":true,"records":231296,"lastAttemptAt":"2026-11-09T04:03:51.2380069+00:00","lastSuccessAt":"2026-11-09T04:03:49.859595+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.2380069+00:00","snapshotPublishedAt":"2026-11-09T03:33:06+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}