{"id":"CVE-2026-89720","revision":null,"records":[{"revision":"cae5f49b5eec48638c89a75ca6c2d42f","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89720","aliases":[],"title":"ubifs: fix out-of-bounds read in signature length check","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nubifs: fix out-of-bounds read in signature length check\n\nubifs_sb_verify_signature() bounds the on-disk ubifs_sig_node->len field\nbefore handing the signature payload to verify_pkcs7_signature(), but the\ncheck has the wrong sign:\n\n\tif (le32_to_cpu(signode->len) > snod->len + sizeof(struct ubifs_sig_node))\n\nThe signature bytes start sizeof(struct ubifs_sig_node) (UBIFS_SIG_NODE_SZ,\n64 bytes) into the node, so the payload is at most\n\n\tsnod->len - sizeof(struct ubifs_sig_node)\n\nbytes long. Adding the header size instead of subtracting it accepts a\ndeclared length up to 2 * UBIFS_SIG_NODE_SZ larger than the node actually\nholds -- past the end of c->sbuf, which is vmalloc(c->leb_size).\nverify_pkcs7_signature() -> pkcs7_parse_message() -> asn1_ber_decoder()\nis then handed that inflated length and reads beyond the allocation while\nwalking the DER headers. The node length comes straight from the mounted\nimage, so a crafted signed UBIFS image reaches this via\nubifs_read_superblock() before the signature is cryptographically checked.\n\nsnod->len is guaranteed to be >= UBIFS_SIG_NODE_SZ by the node scanner\n(c->ranges[UBIFS_SIG_NODE].min_len == UBIFS_SIG_NODE_SZ), so the corrected\nsubtraction cannot underflow. Legitimately signed images are unaffected: a\ncorrect superblock never declares a signature longer than the node it is\nembedded in.","state":0,"publishedAt":"2026-09-11T19:46:32.923+00:00","modifiedAt":"2026-10-19T08:51:33.033+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/ubifs/auth.c\"\n ],\n \"versions\": [\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"ab7405bd86331cc2dbc8201699d4adc33bea75e7\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"11abc34698cb3172badf8aa12e623f1bac98bbd8\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"8cc3da72cf57acb4b77442ea8cec48425dff7c06\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"37a9d25a563f5f9103282954ce573c4a61321e7c\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"f76b79d6e42af20682495bccd22f72c7164b0018\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"a1dc246f98bb94233effa4fa3ec7bf84700bb7d1\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"83e1aa9f5f906c9b1f4949d0521f0f950a159d96\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"817aa094842dfc3a6b98c9582d4a647827f66201\",\n \"lessThan\": \"95d27c1708bb6e8823c8e7c623f9abc2a91bf4bf\",\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/ubifs/auth.c\"\n ],\n \"versions\": [\n {\n \"version\": \"5.3\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"5.3\",\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:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","score":7.7,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/ab7405bd86331cc2dbc8201699d4adc33bea75e7","https://git.kernel.org/stable/c/11abc34698cb3172badf8aa12e623f1bac98bbd8","https://git.kernel.org/stable/c/8cc3da72cf57acb4b77442ea8cec48425dff7c06","https://git.kernel.org/stable/c/37a9d25a563f5f9103282954ce573c4a61321e7c","https://git.kernel.org/stable/c/f76b79d6e42af20682495bccd22f72c7164b0018","https://git.kernel.org/stable/c/a1dc246f98bb94233effa4fa3ec7bf84700bb7d1","https://git.kernel.org/stable/c/83e1aa9f5f906c9b1f4949d0521f0f950a159d96","https://git.kernel.org/stable/c/95d27c1708bb6e8823c8e7c623f9abc2a91bf4bf"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89720","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89720","identifiers":["CVE-2026-89720"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-09T04:03:51.7811525+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-09T04:03:51.7811525+00:00","lastSuccessAt":"2026-11-09T04:03:51.9477173+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.9477231+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-24e6fde7b744113daefb8f6135035fb8a5c69c9617c9c0d40574a0376532ffd3-246bcd291098e4bae24ec491a133b97526d1f4514f8eb34817e1ec280d43b276","complete":true,"records":421286,"lastAttemptAt":"2026-11-09T04:02:14.2951792+00:00","lastSuccessAt":"2026-11-09T04:02:14.2751612+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:02:14.2951792+00:00","snapshotPublishedAt":"2026-11-09T03:29:47+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-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}]}