{"id":"CVE-2026-74583","revision":null,"records":[{"revision":"9a0eb32a5a974b058054c334704cc733","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74583","aliases":[],"title":"net/sched: cls_route: fix fastmap use-after-free on filter","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_route: fix fastmap use-after-free on filter\n\nThe route4 classifier maintains a 16-slot fastmap cache that stores raw\nstruct route4_filter pointers indexed by (id, iif). The reader\n(route4_classify) populates this cache via route4_set_fastmap() for every\nclassified packet that hits a filter. The writer (route4_delete,\nroute4_change) clears the cache via route4_reset_fastmap() before\nRCU-deferred kfree of the filter.\n\nThis creates a UAF race:\n 1. Reader walks the RCU-protected bucket chain, finds filter f\n 2. Writer unlinks f, calls route4_reset_fastmap(), then tcf_queue_work()\n 3. Reader calls route4_set_fastmap() and writes f into the cache\n *after* the writer's reset, caching a pointer about to be freed\n 4. After the RCU grace period, kfree(f) executes\n 5. Next classified packet on the same (id, iif) tuple hits the stale\n fastmap entry and reads f->res from freed memory\n\nReproduced with an mdelay(100) accelerator in route4_set_fastmap() and a\nconcurrent add/delete stress test (provided by both zdi and Santosh).\nBoth triggered KASAN slab-use-after-free reports in the route4 fastmap\npaths.\n\nFix:\nIntroduce a per-filter boolean dying flag to suppress stale fastmap\nrepublishing by in-flight readers.","state":0,"publishedAt":"2026-08-21T16:31:55.886+00:00","modifiedAt":"2026-10-16T19:05:58.388+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/sched/cls_route.c\"\n ],\n \"versions\": [\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"7897198b26445b4009a057bda1986b94a99e5d5f\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"820f083c294ad6d319c02a7d43294f2ed2565139\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"5ec9001be6d0eb527251125632ec8fe88278897f\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"b969984b2bdc85d721ce4047cd270cd37ec705a2\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"a17f636c9330eac879822ce29f998e5abd1b72c1\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"0e7a8cf8895b06d07c7311f028eba16ad742b9bc\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"ae9aff87025219005a2d16b4fe83d6f24643e50d\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"1109c00547fc66df45b9ff923544be4c1e1bec13\",\n \"lessThan\": \"47d7f7051253bdc02b1d245d87e38f16d31a74df\",\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/sched/cls_route.c\"\n ],\n \"versions\": [\n {\n \"version\": \"3.18\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"3.18\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.265\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.216\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.183\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.152\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.104\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.45\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.1.9\",\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:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/7897198b26445b4009a057bda1986b94a99e5d5f","https://git.kernel.org/stable/c/820f083c294ad6d319c02a7d43294f2ed2565139","https://git.kernel.org/stable/c/5ec9001be6d0eb527251125632ec8fe88278897f","https://git.kernel.org/stable/c/b969984b2bdc85d721ce4047cd270cd37ec705a2","https://git.kernel.org/stable/c/a17f636c9330eac879822ce29f998e5abd1b72c1","https://git.kernel.org/stable/c/0e7a8cf8895b06d07c7311f028eba16ad742b9bc","https://git.kernel.org/stable/c/ae9aff87025219005a2d16b4fe83d6f24643e50d","https://git.kernel.org/stable/c/47d7f7051253bdc02b1d245d87e38f16d31a74df"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74583","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74583","identifiers":["CVE-2026-74583"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-09T08:02:26.2193293+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-09T08:02:26.2193293+00:00","lastSuccessAt":"2026-11-09T08:02:26.3903284+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:26.3903314+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-bac7baae6881807b2b4a9dce5cf5dd63af98be3e5c79f031b11fd288ebb8cee0","complete":true,"records":421301,"lastAttemptAt":"2026-11-09T08:02:25.6827821+00:00","lastSuccessAt":"2026-11-09T07:02:22.9878009+00:00","error":"HttpRequestException","lastVerifiedAt":"2026-11-09T07:02:23.0094052+00:00","snapshotPublishedAt":"2026-11-09T06:27:21+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-0bc6adcd3c0c448aa2e9bc2063d5a999","complete":false,"records":13654,"lastAttemptAt":"2026-11-09T08:14:22.8145543+00:00","lastSuccessAt":"2026-11-09T08:14:22.81+00:00","error":"14 identifier lookups failed; latest failures include HTTP 403. Other identifiers were checked independently.","lastVerifiedAt":"2026-11-09T08:14:22.81+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13684,"expectedIdentifiers":13706,"failedIdentifiers":14},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-09T08:02:26.2193293+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-09T08:02:26.2193293+00:00","lastSuccessAt":"2026-11-09T08:02:26.3910394+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:26.3910397+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-156d67f0b09643159ff4bd684ee896db","complete":true,"records":13666,"lastAttemptAt":"2026-11-09T08:02:26.9587387+00:00","lastSuccessAt":"2026-11-09T07:04:26.209+00:00","error":null,"lastVerifiedAt":"2026-11-09T07:04:26.209+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":"2026-11-09T08:02:26.1458433+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:26.1458433+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":"2026-11-09T08:02:25.8338551+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:25.8338551+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-f6d341f4320a5a0c059c28102ee651c3dd06abc87b84d2bafa4e2a823ec07d35","complete":true,"records":3056,"lastAttemptAt":"2026-11-09T08:02:26.1741996+00:00","lastSuccessAt":"2026-11-09T05:02:23.1539412+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:26.1741996+00:00","snapshotPublishedAt":"2026-11-09T04:47:48+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-32fcf2a839d0d91a36b31c98096d6b8a1a8cc523d64745f8a939e306130e49f2","complete":true,"records":231296,"lastAttemptAt":"2026-11-09T08:02:25.9613255+00:00","lastSuccessAt":"2026-11-09T07:04:23.2641171+00:00","error":null,"lastVerifiedAt":"2026-11-09T08:02:25.9613255+00:00","snapshotPublishedAt":"2026-11-09T06:48:11+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}