{"api_version":"1","generated_at":"2026-07-23T15:37:17+00:00","cve":"CVE-2026-63801","urls":{"html":"https://cve.report/CVE-2026-63801","api":"https://cve.report/api/cve/CVE-2026-63801.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-63801","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63801"},"summary":{"title":"tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix slab-use-after-free Read in tipc_aead_decrypt_done\n\ntipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to\ncrypto_aead_decrypt(req) without taking a reference on the netns, unlike\nthe encrypt path. When crypto_aead_decrypt() is offloaded asynchronously\n(e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs\ntipc_aead_decrypt_done() later. If the bearer's netns is torn down in the\nmeantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the\nper-netns tipc_crypto, and the completion then reads it:\ntipc_aead_decrypt_done() dereferences aead->crypto->stats and\naead->crypto->net, and tipc_crypto_rcv_complete() dereferences\naead->crypto->aead[] and the node table -- reading freed memory.\n\nDecoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO):\n\n  BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n  Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51\n  Workqueue: events_unbound\n  Call Trace:\n   tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n   process_one_work (kernel/workqueue.c:3314)\n   worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)\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  Allocated by task 169:\n   __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)\n   tipc_crypto_start (net/tipc/crypto.c:1502)\n   tipc_init_net (net/tipc/core.c:72)\n   ops_init (net/core/net_namespace.c:137)\n   setup_net (net/core/net_namespace.c:446)\n   copy_net_ns (net/core/net_namespace.c:579)\n   create_new_namespaces (kernel/nsproxy.c:132)\n   __x64_sys_unshare (kernel/fork.c:3316)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n\n  Freed by task 8:\n   kfree (mm/slub.c:6566)\n   tipc_exit_net (net/tipc/core.c:119)\n   cleanup_net (net/core/net_namespace.c:704)\n   process_one_work (kernel/workqueue.c:3314)\n   kthread (kernel/kthread.c:436)\n\nThis is the same class of bug that commit e279024617134 (\"net/tipc: fix\nslab-use-after-free Read in tipc_aead_encrypt_done\") fixed for the encrypt\nside. The encrypt path takes maybe_get_net(aead->crypto->net) before\ncrypto_aead_encrypt() and drops it with put_net() on the synchronous\nreturn paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY\nreturn keeps the reference for the async callback to release. The decrypt\npath was left without the equivalent guard.\n\nMirror the encrypt-side fix on the decrypt path: take a net reference\nbefore crypto_aead_decrypt() (failing with -ENODEV and the matching\nbearer put if it cannot be acquired), keep it across the\n-EINPROGRESS/-EBUSY async return, and drop it with put_net() on the\nsynchronous success/error return and at the end of\ntipc_aead_decrypt_done().\n\nReproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is\nflooded with crafted encrypted frames from an unknown peer (driving the\ncluster-key decrypt path) while the bearer's netns is repeatedly torn\ndown. The completion must run asynchronously to outlive\ntipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts\nsynchronously, so the async path was exercised via cryptd offload. The\nunguarded aead->crypto dereference in tipc_aead_decrypt_done() is the\nunpatched upstream path; tipc_aead_decrypt() still lacks\nmaybe_get_net(aead->crypto->net), so the completion can outlive the free\non any config where crypto_aead_decrypt() goes async.\n\nFound by 0sec automated security-research tooling (https://0sec.ai).","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-19 12:16:52","updated_at":"2026-07-20 15:16:46"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/eaca7dae02fab70c8d223cffe03cec1b93249ce2","name":"https://git.kernel.org/stable/c/eaca7dae02fab70c8d223cffe03cec1b93249ce2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/dca7713fe044a2067387948557ea099056e1679e","name":"https://git.kernel.org/stable/c/dca7713fe044a2067387948557ea099056e1679e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1eea5e1820a2f5164d706bd1277bc97ff31ce32d","name":"https://git.kernel.org/stable/c/1eea5e1820a2f5164d706bd1277bc97ff31ce32d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e18769616fd5a90ec1e12aabbba544c488284292","name":"https://git.kernel.org/stable/c/e18769616fd5a90ec1e12aabbba544c488284292","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bda3348872a2ef0d19f2df6aa8cb5025adce2f20","name":"https://git.kernel.org/stable/c/bda3348872a2ef0d19f2df6aa8cb5025adce2f20","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2d1f21419ec121232c916d3a3fc9b6766473a0e7","name":"https://git.kernel.org/stable/c/2d1f21419ec121232c916d3a3fc9b6766473a0e7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0a780653b2a7569a7af9be7d0b00b1251baca63a","name":"https://git.kernel.org/stable/c/0a780653b2a7569a7af9be7d0b00b1251baca63a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/171d31245d11bf84836fad3b394cb465a4d008ec","name":"https://git.kernel.org/stable/c/171d31245d11bf84836fad3b394cb465a4d008ec","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-63801","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63801","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 171d31245d11bf84836fad3b394cb465a4d008ec git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 2d1f21419ec121232c916d3a3fc9b6766473a0e7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 0a780653b2a7569a7af9be7d0b00b1251baca63a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 eaca7dae02fab70c8d223cffe03cec1b93249ce2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 dca7713fe044a2067387948557ea099056e1679e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 e18769616fd5a90ec1e12aabbba544c488284292 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 1eea5e1820a2f5164d706bd1277bc97ff31ce32d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 bda3348872a2ef0d19f2df6aa8cb5025adce2f20 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.5","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.5 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.260 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.211 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.177 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.144 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.95 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.38 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.3 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"63801","cve":"CVE-2026-63801","epss":"0.001770000","percentile":"0.074120000","score_date":"2026-07-20","updated_at":"2026-07-21 00:13:14"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/tipc/crypto.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"171d31245d11bf84836fad3b394cb465a4d008ec","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"2d1f21419ec121232c916d3a3fc9b6766473a0e7","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"0a780653b2a7569a7af9be7d0b00b1251baca63a","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"eaca7dae02fab70c8d223cffe03cec1b93249ce2","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"dca7713fe044a2067387948557ea099056e1679e","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"e18769616fd5a90ec1e12aabbba544c488284292","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"1eea5e1820a2f5164d706bd1277bc97ff31ce32d","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"},{"lessThan":"bda3348872a2ef0d19f2df6aa8cb5025adce2f20","status":"affected","version":"fc1b6d6de2208774efd2a20bf0daddb02d18b1e0","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/tipc/crypto.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.5"},{"lessThan":"5.5","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.260","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.211","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.177","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.144","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.95","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.38","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.3","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.260","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.211","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.177","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.144","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.95","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.38","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.3","versionStartIncluding":"5.5","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"5.5","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix slab-use-after-free Read in tipc_aead_decrypt_done\n\ntipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to\ncrypto_aead_decrypt(req) without taking a reference on the netns, unlike\nthe encrypt path. When crypto_aead_decrypt() is offloaded asynchronously\n(e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs\ntipc_aead_decrypt_done() later. If the bearer's netns is torn down in the\nmeantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the\nper-netns tipc_crypto, and the completion then reads it:\ntipc_aead_decrypt_done() dereferences aead->crypto->stats and\naead->crypto->net, and tipc_crypto_rcv_complete() dereferences\naead->crypto->aead[] and the node table -- reading freed memory.\n\nDecoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO):\n\n  BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n  Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51\n  Workqueue: events_unbound\n  Call Trace:\n   tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n   process_one_work (kernel/workqueue.c:3314)\n   worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)\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  Allocated by task 169:\n   __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)\n   tipc_crypto_start (net/tipc/crypto.c:1502)\n   tipc_init_net (net/tipc/core.c:72)\n   ops_init (net/core/net_namespace.c:137)\n   setup_net (net/core/net_namespace.c:446)\n   copy_net_ns (net/core/net_namespace.c:579)\n   create_new_namespaces (kernel/nsproxy.c:132)\n   __x64_sys_unshare (kernel/fork.c:3316)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n\n  Freed by task 8:\n   kfree (mm/slub.c:6566)\n   tipc_exit_net (net/tipc/core.c:119)\n   cleanup_net (net/core/net_namespace.c:704)\n   process_one_work (kernel/workqueue.c:3314)\n   kthread (kernel/kthread.c:436)\n\nThis is the same class of bug that commit e279024617134 (\"net/tipc: fix\nslab-use-after-free Read in tipc_aead_encrypt_done\") fixed for the encrypt\nside. The encrypt path takes maybe_get_net(aead->crypto->net) before\ncrypto_aead_encrypt() and drops it with put_net() on the synchronous\nreturn paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY\nreturn keeps the reference for the async callback to release. The decrypt\npath was left without the equivalent guard.\n\nMirror the encrypt-side fix on the decrypt path: take a net reference\nbefore crypto_aead_decrypt() (failing with -ENODEV and the matching\nbearer put if it cannot be acquired), keep it across the\n-EINPROGRESS/-EBUSY async return, and drop it with put_net() on the\nsynchronous success/error return and at the end of\ntipc_aead_decrypt_done().\n\nReproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is\nflooded with crafted encrypted frames from an unknown peer (driving the\ncluster-key decrypt path) while the bearer's netns is repeatedly torn\ndown. The completion must run asynchronously to outlive\ntipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts\nsynchronously, so the async path was exercised via cryptd offload. The\nunguarded aead->crypto dereference in tipc_aead_decrypt_done() is the\nunpatched upstream path; tipc_aead_decrypt() still lacks\nmaybe_get_net(aead->crypto->net), so the completion can outlive the free\non any config where crypto_aead_decrypt() goes async.\n\nFound by 0sec automated security-research tooling (https://0sec.ai)."}],"metrics":[{"cvssV3_1":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-07-20T13:40:11.527Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/171d31245d11bf84836fad3b394cb465a4d008ec"},{"url":"https://git.kernel.org/stable/c/2d1f21419ec121232c916d3a3fc9b6766473a0e7"},{"url":"https://git.kernel.org/stable/c/0a780653b2a7569a7af9be7d0b00b1251baca63a"},{"url":"https://git.kernel.org/stable/c/eaca7dae02fab70c8d223cffe03cec1b93249ce2"},{"url":"https://git.kernel.org/stable/c/dca7713fe044a2067387948557ea099056e1679e"},{"url":"https://git.kernel.org/stable/c/e18769616fd5a90ec1e12aabbba544c488284292"},{"url":"https://git.kernel.org/stable/c/1eea5e1820a2f5164d706bd1277bc97ff31ce32d"},{"url":"https://git.kernel.org/stable/c/bda3348872a2ef0d19f2df6aa8cb5025adce2f20"}],"title":"tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-63801","datePublished":"2026-07-19T12:02:07.457Z","dateReserved":"2026-07-19T07:54:57.013Z","dateUpdated":"2026-07-20T13:40:11.527Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-19 12:16:52","lastModifiedDate":"2026-07-20 15:16:46","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"63801","Ordinal":"1","Title":"tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done","CVE":"CVE-2026-63801","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"63801","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix slab-use-after-free Read in tipc_aead_decrypt_done\n\ntipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to\ncrypto_aead_decrypt(req) without taking a reference on the netns, unlike\nthe encrypt path. When crypto_aead_decrypt() is offloaded asynchronously\n(e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs\ntipc_aead_decrypt_done() later. If the bearer's netns is torn down in the\nmeantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the\nper-netns tipc_crypto, and the completion then reads it:\ntipc_aead_decrypt_done() dereferences aead->crypto->stats and\naead->crypto->net, and tipc_crypto_rcv_complete() dereferences\naead->crypto->aead[] and the node table -- reading freed memory.\n\nDecoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO):\n\n  BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n  Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51\n  Workqueue: events_unbound\n  Call Trace:\n   tipc_aead_decrypt_done (net/tipc/crypto.c:999)\n   process_one_work (kernel/workqueue.c:3314)\n   worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)\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  Allocated by task 169:\n   __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)\n   tipc_crypto_start (net/tipc/crypto.c:1502)\n   tipc_init_net (net/tipc/core.c:72)\n   ops_init (net/core/net_namespace.c:137)\n   setup_net (net/core/net_namespace.c:446)\n   copy_net_ns (net/core/net_namespace.c:579)\n   create_new_namespaces (kernel/nsproxy.c:132)\n   __x64_sys_unshare (kernel/fork.c:3316)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n\n  Freed by task 8:\n   kfree (mm/slub.c:6566)\n   tipc_exit_net (net/tipc/core.c:119)\n   cleanup_net (net/core/net_namespace.c:704)\n   process_one_work (kernel/workqueue.c:3314)\n   kthread (kernel/kthread.c:436)\n\nThis is the same class of bug that commit e279024617134 (\"net/tipc: fix\nslab-use-after-free Read in tipc_aead_encrypt_done\") fixed for the encrypt\nside. The encrypt path takes maybe_get_net(aead->crypto->net) before\ncrypto_aead_encrypt() and drops it with put_net() on the synchronous\nreturn paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY\nreturn keeps the reference for the async callback to release. The decrypt\npath was left without the equivalent guard.\n\nMirror the encrypt-side fix on the decrypt path: take a net reference\nbefore crypto_aead_decrypt() (failing with -ENODEV and the matching\nbearer put if it cannot be acquired), keep it across the\n-EINPROGRESS/-EBUSY async return, and drop it with put_net() on the\nsynchronous success/error return and at the end of\ntipc_aead_decrypt_done().\n\nReproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is\nflooded with crafted encrypted frames from an unknown peer (driving the\ncluster-key decrypt path) while the bearer's netns is repeatedly torn\ndown. The completion must run asynchronously to outlive\ntipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts\nsynchronously, so the async path was exercised via cryptd offload. The\nunguarded aead->crypto dereference in tipc_aead_decrypt_done() is the\nunpatched upstream path; tipc_aead_decrypt() still lacks\nmaybe_get_net(aead->crypto->net), so the completion can outlive the free\non any config where crypto_aead_decrypt() goes async.\n\nFound by 0sec automated security-research tooling (https://0sec.ai).","Type":"Description","Title":"tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done"}]}}}