{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-31533", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.113Z", "datePublished": "2026-04-23T15:11:06.955Z", "dateUpdated": "2026-08-05T12:23:20.687Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:23:20.687Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: fix use-after-free in -EBUSY error path of tls_do_encryption\n\nThe -EBUSY handling in tls_do_encryption(), introduced by commit\n859054147318 (\"net: tls: handle backlogging of crypto requests\"), has\na use-after-free due to double cleanup of encrypt_pending and the\nscatterlist entry.\n\nWhen crypto_aead_encrypt() returns -EBUSY, the request is enqueued to\nthe cryptd backlog and the async callback tls_encrypt_done() will be\ninvoked upon completion. That callback unconditionally restores the\nscatterlist entry (sge->offset, sge->length) and decrements\nctx->encrypt_pending. However, if tls_encrypt_async_wait() returns an\nerror, the synchronous error path in tls_do_encryption() performs the\nsame cleanup again, double-decrementing encrypt_pending and\ndouble-restoring the scatterlist.\n\nThe double-decrement corrupts the encrypt_pending sentinel (initialized\nto 1), making tls_encrypt_async_wait() permanently skip the wait for\npending async callbacks. A subsequent sendmsg can then free the\ntls_rec via bpf_exec_tx_verdict() while a cryptd callback is still\npending, resulting in a use-after-free when the callback fires on the\nfreed record.\n\nFix this by skipping the synchronous cleanup when the -EBUSY async\nwait returns an error, since the callback has already handled\nencrypt_pending and sge restoration." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is in the kTLS TX path reached when a kTLS-enabled network service sends TLS records to a peer; a remote client can plausibly trigger repeated encrypted responses and connection errors over the network.\nAC:L - The vulnerable condition is the normal async crypto backlog/error path, and an attacker can drive request volume and connection aborts/retries rather than depending on an uncontrollable race. Under the required rule, the defensible choice for a kTLS UAF is low complexity.\nPR:N - In the network-service scenario, the attacker only needs to connect to and interact with the exposed TLS service; no local account or kernel capability is required.\nUI:N - No user interaction is required once the vulnerable kTLS-enabled service is reachable; the attacker can trigger sends by network requests.\nS:U - The corruption is within the kernel handling of the same host and does not cross a separate security authority such as a VM boundary.\nC:H - This is a use-after-free of a heap-allocated tls_rec used later by an async crypto callback, giving memory corruption potential consistent with kernel information disclosure.\nI:H - The async callback writes through fields in the freed record, so heap reuse can turn the UAF into kernel memory corruption/control-flow impact.\nA:H - Even without full exploitation, the stale callback can dereference or modify freed memory and crash or oops the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/tls/tls_sw.c" ], "versions": [ { "version": "3ade391adc584f17b5570fd205de3ad029090368", "lessThan": "414fc5e5a5aff776c150f1b86770e0a25a35df3a", "status": "affected", "versionType": "git" }, { "version": "cd1bbca03f3c1d845ce274c0d0a66de8e5929f72", "lessThan": "02f3ecadb23558bbe068e6504118f1b712d4ece0", "status": "affected", "versionType": "git" }, { "version": "13eca403876bbea3716e82cdfe6f1e6febb38754", "lessThan": "0e43e0a3c94044acc74b8e0927c27972eb5a59e8", "status": "affected", "versionType": "git" }, { "version": "8590541473188741055d27b955db0777569438e3", "lessThan": "aa9facde6c5005205874c37db3fd25799d741baf", "status": "affected", "versionType": "git" }, { "version": "8590541473188741055d27b955db0777569438e3", "lessThan": "5d70eb25b41e9b010828cd12818b06a0c3b04412", "status": "affected", "versionType": "git" }, { "version": "8590541473188741055d27b955db0777569438e3", "lessThan": "2694d408b0e595024e0fc1d64ff9db0358580f74", "status": "affected", "versionType": "git" }, { "version": "8590541473188741055d27b955db0777569438e3", "lessThan": "a9b8b18364fffce4c451e6f6fd218fa4ab646705", "status": "affected", "versionType": "git" }, { "version": "ab6397f072e5097f267abf5cb08a8004e6b17694", "status": "affected", "versionType": "git" }, { "version": "5.15.160", "lessThan": "5.15.203", "status": "affected", "versionType": "semver" }, { "version": "6.1.84", "lessThan": "6.1.169", "status": "affected", "versionType": "semver" }, { "version": "6.6.18", "lessThan": "6.6.135", "status": "affected", "versionType": "semver" }, { "version": "6.7.6", "lessThan": "6.8", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/tls/tls_sw.c" ], "versions": [ { "version": "6.8", "status": "affected" }, { "version": "0", "lessThan": "6.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.169", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.135", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.82", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.23", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.13", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.160", "versionEndExcluding": "5.15.203" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.84", "versionEndExcluding": "6.1.169" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.18", "versionEndExcluding": "6.6.135" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.12.82" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.18.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.19.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.0" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7.6" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/414fc5e5a5aff776c150f1b86770e0a25a35df3a" }, { "url": "https://git.kernel.org/stable/c/02f3ecadb23558bbe068e6504118f1b712d4ece0" }, { "url": "https://git.kernel.org/stable/c/0e43e0a3c94044acc74b8e0927c27972eb5a59e8" }, { "url": "https://git.kernel.org/stable/c/aa9facde6c5005205874c37db3fd25799d741baf" }, { "url": "https://git.kernel.org/stable/c/5d70eb25b41e9b010828cd12818b06a0c3b04412" }, { "url": "https://git.kernel.org/stable/c/2694d408b0e595024e0fc1d64ff9db0358580f74" }, { "url": "https://git.kernel.org/stable/c/a9b8b18364fffce4c451e6f6fd218fa4ab646705" } ], "title": "net/tls: fix use-after-free in -EBUSY error path of tls_do_encryption", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "x_adpType": "supplier", 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