{"api_version":"1","generated_at":"2026-06-08T18:27:54+00:00","cve":"CVE-2026-46274","urls":{"html":"https://cve.report/CVE-2026-46274","api":"https://cve.report/api/cve/CVE-2026-46274.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-46274","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-46274"},"summary":{"title":"io-wq: check that the predecessor is hashed in io_wq_remove_pending()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio-wq: check that the predecessor is hashed in io_wq_remove_pending()\n\nio_wq_remove_pending() needs to fix up wq->hash_tail[] if the cancelled\nwork was the tail of its hash bucket. When doing this, it checks whether\nthe preceding entry in acct->work_list has the same hash value, but\nnever checks that the predecessor is hashed at all. io_get_work_hash()\nis simply atomic_read(&work->flags) >> IO_WQ_HASH_SHIFT, and the hash\nbits are never set for non-hashed work, so it returns 0. Thus, when a\nhashed bucket-0 work is cancelled while a non-hashed work is its list\npredecessor, the check spuriously passes and a pointer to the non-hashed\nio_kiocb is stored in wq->hash_tail[0].\n\nBecause non-hashed work is dequeued via the fast path in\nio_get_next_work(), which never touches hash_tail[], the stale pointer\nis never cleared. Therefore, after the non-hashed io_kiocb completes and\nis freed back to req_cachep, wq->hash_tail[0] is a dangling pointer. The\nio_wq is per-task (tctx->io_wq) and survives ring open/close, so the\ndangling pointer persists for the lifetime of the task; the next hashed\nbucket-0 enqueue dereferences it in io_wq_insert_work() and\nwq_list_add_after() writes through freed memory.\n\nAdd the missing io_wq_is_hashed() check so a non-hashed predecessor\nnever inherits a hash_tail[] slot.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-08 16:16:40","updated_at":"2026-06-08 16:16:40"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/5a20ebf0c81b61f5ea3b1b529c100cad69b9f603","name":"https://git.kernel.org/stable/c/5a20ebf0c81b61f5ea3b1b529c100cad69b9f603","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d376c131af7c7739a87ff037ed2fdb67c2542c8a","name":"https://git.kernel.org/stable/c/d376c131af7c7739a87ff037ed2fdb67c2542c8a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d6bda9df0c0a3080804181464d5c0f4d78a4e769","name":"https://git.kernel.org/stable/c/d6bda9df0c0a3080804181464d5c0f4d78a4e769","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/252c5051dba9c709b6a72f2866f93e5e618b3f06","name":"https://git.kernel.org/stable/c/252c5051dba9c709b6a72f2866f93e5e618b3f06","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc","name":"https://git.kernel.org/stable/c/d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-46274","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46274","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 204361a77f4018627addd4a06877448f088ddfc0 d6bda9df0c0a3080804181464d5c0f4d78a4e769 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 204361a77f4018627addd4a06877448f088ddfc0 5a20ebf0c81b61f5ea3b1b529c100cad69b9f603 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 204361a77f4018627addd4a06877448f088ddfc0 252c5051dba9c709b6a72f2866f93e5e618b3f06 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 204361a77f4018627addd4a06877448f088ddfc0 d376c131af7c7739a87ff037ed2fdb67c2542c8a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 204361a77f4018627addd4a06877448f088ddfc0 d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 13f35a2c0fd5c6a4fcd8903542b053bcc914fcf5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.8.6 5.9 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.9","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.9 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.141 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.91 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.33 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.10 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1-rc4 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["io_uring/io-wq.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d6bda9df0c0a3080804181464d5c0f4d78a4e769","status":"affected","version":"204361a77f4018627addd4a06877448f088ddfc0","versionType":"git"},{"lessThan":"5a20ebf0c81b61f5ea3b1b529c100cad69b9f603","status":"affected","version":"204361a77f4018627addd4a06877448f088ddfc0","versionType":"git"},{"lessThan":"252c5051dba9c709b6a72f2866f93e5e618b3f06","status":"affected","version":"204361a77f4018627addd4a06877448f088ddfc0","versionType":"git"},{"lessThan":"d376c131af7c7739a87ff037ed2fdb67c2542c8a","status":"affected","version":"204361a77f4018627addd4a06877448f088ddfc0","versionType":"git"},{"lessThan":"d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc","status":"affected","version":"204361a77f4018627addd4a06877448f088ddfc0","versionType":"git"},{"status":"affected","version":"13f35a2c0fd5c6a4fcd8903542b053bcc914fcf5","versionType":"git"},{"lessThan":"5.9","status":"affected","version":"5.8.6","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["io_uring/io-wq.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.9"},{"lessThan":"5.9","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.141","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.91","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.33","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1-rc4","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.141","versionStartIncluding":"5.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.91","versionStartIncluding":"5.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.33","versionStartIncluding":"5.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.10","versionStartIncluding":"5.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1-rc4","versionStartIncluding":"5.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8.6","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nio-wq: check that the predecessor is hashed in io_wq_remove_pending()\n\nio_wq_remove_pending() needs to fix up wq->hash_tail[] if the cancelled\nwork was the tail of its hash bucket. When doing this, it checks whether\nthe preceding entry in acct->work_list has the same hash value, but\nnever checks that the predecessor is hashed at all. io_get_work_hash()\nis simply atomic_read(&work->flags) >> IO_WQ_HASH_SHIFT, and the hash\nbits are never set for non-hashed work, so it returns 0. Thus, when a\nhashed bucket-0 work is cancelled while a non-hashed work is its list\npredecessor, the check spuriously passes and a pointer to the non-hashed\nio_kiocb is stored in wq->hash_tail[0].\n\nBecause non-hashed work is dequeued via the fast path in\nio_get_next_work(), which never touches hash_tail[], the stale pointer\nis never cleared. Therefore, after the non-hashed io_kiocb completes and\nis freed back to req_cachep, wq->hash_tail[0] is a dangling pointer. The\nio_wq is per-task (tctx->io_wq) and survives ring open/close, so the\ndangling pointer persists for the lifetime of the task; the next hashed\nbucket-0 enqueue dereferences it in io_wq_insert_work() and\nwq_list_add_after() writes through freed memory.\n\nAdd the missing io_wq_is_hashed() check so a non-hashed predecessor\nnever inherits a hash_tail[] slot."}],"providerMetadata":{"dateUpdated":"2026-06-08T14:30:53.323Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d6bda9df0c0a3080804181464d5c0f4d78a4e769"},{"url":"https://git.kernel.org/stable/c/5a20ebf0c81b61f5ea3b1b529c100cad69b9f603"},{"url":"https://git.kernel.org/stable/c/252c5051dba9c709b6a72f2866f93e5e618b3f06"},{"url":"https://git.kernel.org/stable/c/d376c131af7c7739a87ff037ed2fdb67c2542c8a"},{"url":"https://git.kernel.org/stable/c/d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc"}],"title":"io-wq: check that the predecessor is hashed in io_wq_remove_pending()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-46274","datePublished":"2026-06-08T14:30:53.323Z","dateReserved":"2026-05-13T15:03:33.109Z","dateUpdated":"2026-06-08T14:30:53.323Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-08 16:16:40","lastModifiedDate":"2026-06-08 16:16:40","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"46274","Ordinal":"1","Title":"io-wq: check that the predecessor is hashed in io_wq_remove_pend","CVE":"CVE-2026-46274","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"46274","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nio-wq: check that the predecessor is hashed in io_wq_remove_pending()\n\nio_wq_remove_pending() needs to fix up wq->hash_tail[] if the cancelled\nwork was the tail of its hash bucket. When doing this, it checks whether\nthe preceding entry in acct->work_list has the same hash value, but\nnever checks that the predecessor is hashed at all. io_get_work_hash()\nis simply atomic_read(&work->flags) >> IO_WQ_HASH_SHIFT, and the hash\nbits are never set for non-hashed work, so it returns 0. Thus, when a\nhashed bucket-0 work is cancelled while a non-hashed work is its list\npredecessor, the check spuriously passes and a pointer to the non-hashed\nio_kiocb is stored in wq->hash_tail[0].\n\nBecause non-hashed work is dequeued via the fast path in\nio_get_next_work(), which never touches hash_tail[], the stale pointer\nis never cleared. Therefore, after the non-hashed io_kiocb completes and\nis freed back to req_cachep, wq->hash_tail[0] is a dangling pointer. The\nio_wq is per-task (tctx->io_wq) and survives ring open/close, so the\ndangling pointer persists for the lifetime of the task; the next hashed\nbucket-0 enqueue dereferences it in io_wq_insert_work() and\nwq_list_add_after() writes through freed memory.\n\nAdd the missing io_wq_is_hashed() check so a non-hashed predecessor\nnever inherits a hash_tail[] slot.","Type":"Description","Title":"io-wq: check that the predecessor is hashed in io_wq_remove_pend"}]}}}