{"api_version":"1","generated_at":"2026-08-06T02:59:02+00:00","cve":"CVE-2026-64579","urls":{"html":"https://cve.report/CVE-2026-64579","api":"https://cve.report/api/cve/CVE-2026-64579.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64579","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64579"},"summary":{"title":"xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert\n\nxfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert\nloop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or\nfail. But its guard is inverted: it skips policies with prefixlen <\nthreshold and preallocates for the rest.\n\nprefixlen < threshold is exactly when policy_hash_bysel() returns NULL and\nthe reinsert takes the allocating xfrm_policy_inexact_insert() path. So the\nloop preallocates for the exact policies (which never allocate) and skips\nthe inexact ones, whose bin/node is then allocated GFP_ATOMIC during\nreinsert. On failure the error path only WARN_ONCE()s and continues,\nleaving a poisoned bydst node; the next rebuild's hlist_del_rcu()\ndereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure,\ndeterministic via failslab.\n\nInvert the guard so preallocation covers exactly the reinserted policies;\nthe reinsert then allocates nothing and cannot fail.\n\nCrash:\n  Oops: general protection fault, probably for non-canonical address\n  0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n  KASAN: maybe wild-memory-access in range [0xdead...]\n  ...\n  Workqueue: events xfrm_hash_rebuild\n  RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190\n  RAX: dead000000000122   (LIST_POISON2 + offset)\n  ...\n  Call Trace:\n   hlist_del_rcu (include/linux/rculist.h:599)\n   xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)\n   process_one_work (kernel/workqueue.c:3322)\n   worker_thread (kernel/workqueue.c:3486)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n   ...\n  Kernel panic - not syncing: Fatal exception in interrupt","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-05 08:16:37","updated_at":"2026-08-05 08:16:37"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/7acc5ed2f33608a3d83b64f50a5766843b6e2485","name":"https://git.kernel.org/stable/c/7acc5ed2f33608a3d83b64f50a5766843b6e2485","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6aa3796d18a9fda953ad76a62b57bf6c145cb9ef","name":"https://git.kernel.org/stable/c/6aa3796d18a9fda953ad76a62b57bf6c145cb9ef","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/94c00391a5117530188334f740ce26d3f1256190","name":"https://git.kernel.org/stable/c/94c00391a5117530188334f740ce26d3f1256190","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f38f8cce2f7e79775b3db7e8a5eacda04ac908e4","name":"https://git.kernel.org/stable/c/f38f8cce2f7e79775b3db7e8a5eacda04ac908e4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d9d9cc21cc90014724a14c447e3d587be9447107","name":"https://git.kernel.org/stable/c/d9d9cc21cc90014724a14c447e3d587be9447107","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64579","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64579","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 24969facd704a5f0dd8e08da86bf32a9ce972bee d9d9cc21cc90014724a14c447e3d587be9447107 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 24969facd704a5f0dd8e08da86bf32a9ce972bee 94c00391a5117530188334f740ce26d3f1256190 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 24969facd704a5f0dd8e08da86bf32a9ce972bee 7acc5ed2f33608a3d83b64f50a5766843b6e2485 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 24969facd704a5f0dd8e08da86bf32a9ce972bee 6aa3796d18a9fda953ad76a62b57bf6c145cb9ef git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 24969facd704a5f0dd8e08da86bf32a9ce972bee f38f8cce2f7e79775b3db7e8a5eacda04ac908e4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.0","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.0 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.148 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.101 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc4 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64579","cve":"CVE-2026-64579","epss":"0.001560000","percentile":"0.052670000","score_date":"2026-08-05","updated_at":"2026-08-06 00:00:32"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/xfrm/xfrm_policy.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d9d9cc21cc90014724a14c447e3d587be9447107","status":"affected","version":"24969facd704a5f0dd8e08da86bf32a9ce972bee","versionType":"git"},{"lessThan":"94c00391a5117530188334f740ce26d3f1256190","status":"affected","version":"24969facd704a5f0dd8e08da86bf32a9ce972bee","versionType":"git"},{"lessThan":"7acc5ed2f33608a3d83b64f50a5766843b6e2485","status":"affected","version":"24969facd704a5f0dd8e08da86bf32a9ce972bee","versionType":"git"},{"lessThan":"6aa3796d18a9fda953ad76a62b57bf6c145cb9ef","status":"affected","version":"24969facd704a5f0dd8e08da86bf32a9ce972bee","versionType":"git"},{"lessThan":"f38f8cce2f7e79775b3db7e8a5eacda04ac908e4","status":"affected","version":"24969facd704a5f0dd8e08da86bf32a9ce972bee","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/xfrm/xfrm_policy.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.0"},{"lessThan":"5.0","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.148","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.101","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc4","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.148","versionStartIncluding":"5.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.101","versionStartIncluding":"5.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"5.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"5.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc4","versionStartIncluding":"5.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert\n\nxfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert\nloop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or\nfail. But its guard is inverted: it skips policies with prefixlen <\nthreshold and preallocates for the rest.\n\nprefixlen < threshold is exactly when policy_hash_bysel() returns NULL and\nthe reinsert takes the allocating xfrm_policy_inexact_insert() path. So the\nloop preallocates for the exact policies (which never allocate) and skips\nthe inexact ones, whose bin/node is then allocated GFP_ATOMIC during\nreinsert. On failure the error path only WARN_ONCE()s and continues,\nleaving a poisoned bydst node; the next rebuild's hlist_del_rcu()\ndereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure,\ndeterministic via failslab.\n\nInvert the guard so preallocation covers exactly the reinserted policies;\nthe reinsert then allocates nothing and cannot fail.\n\nCrash:\n  Oops: general protection fault, probably for non-canonical address\n  0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n  KASAN: maybe wild-memory-access in range [0xdead...]\n  ...\n  Workqueue: events xfrm_hash_rebuild\n  RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190\n  RAX: dead000000000122   (LIST_POISON2 + offset)\n  ...\n  Call Trace:\n   hlist_del_rcu (include/linux/rculist.h:599)\n   xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)\n   process_one_work (kernel/workqueue.c:3322)\n   worker_thread (kernel/workqueue.c:3486)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n   ...\n  Kernel panic - not syncing: Fatal exception in interrupt"}],"providerMetadata":{"dateUpdated":"2026-08-05T08:09:34.346Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d9d9cc21cc90014724a14c447e3d587be9447107"},{"url":"https://git.kernel.org/stable/c/94c00391a5117530188334f740ce26d3f1256190"},{"url":"https://git.kernel.org/stable/c/7acc5ed2f33608a3d83b64f50a5766843b6e2485"},{"url":"https://git.kernel.org/stable/c/6aa3796d18a9fda953ad76a62b57bf6c145cb9ef"},{"url":"https://git.kernel.org/stable/c/f38f8cce2f7e79775b3db7e8a5eacda04ac908e4"}],"title":"xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64579","datePublished":"2026-08-05T08:09:34.346Z","dateReserved":"2026-07-19T15:36:31.798Z","dateUpdated":"2026-08-05T08:09:34.346Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-05 08:16:37","lastModifiedDate":"2026-08-05 08:16:37","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64579","Ordinal":"1","Title":"xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild ","CVE":"CVE-2026-64579","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64579","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert\n\nxfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert\nloop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or\nfail. But its guard is inverted: it skips policies with prefixlen <\nthreshold and preallocates for the rest.\n\nprefixlen < threshold is exactly when policy_hash_bysel() returns NULL and\nthe reinsert takes the allocating xfrm_policy_inexact_insert() path. So the\nloop preallocates for the exact policies (which never allocate) and skips\nthe inexact ones, whose bin/node is then allocated GFP_ATOMIC during\nreinsert. On failure the error path only WARN_ONCE()s and continues,\nleaving a poisoned bydst node; the next rebuild's hlist_del_rcu()\ndereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure,\ndeterministic via failslab.\n\nInvert the guard so preallocation covers exactly the reinserted policies;\nthe reinsert then allocates nothing and cannot fail.\n\nCrash:\n  Oops: general protection fault, probably for non-canonical address\n  0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI\n  KASAN: maybe wild-memory-access in range [0xdead...]\n  ...\n  Workqueue: events xfrm_hash_rebuild\n  RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190\n  RAX: dead000000000122   (LIST_POISON2 + offset)\n  ...\n  Call Trace:\n   hlist_del_rcu (include/linux/rculist.h:599)\n   xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)\n   process_one_work (kernel/workqueue.c:3322)\n   worker_thread (kernel/workqueue.c:3486)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n   ...\n  Kernel panic - not syncing: Fatal exception in interrupt","Type":"Description","Title":"xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild "}]}}}