{"cve":"CVE-2026-31533","nvd":{"published":"2026-04-23T18:16:26.857","modified":"2026-10-19T19:17:59.240","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/02f3ecadb23558bbe068e6504118f1b712d4ece0","https://git.kernel.org/stable/c/0e43e0a3c94044acc74b8e0927c27972eb5a59e8","https://git.kernel.org/stable/c/2694d408b0e595024e0fc1d64ff9db0358580f74","https://git.kernel.org/stable/c/414fc5e5a5aff776c150f1b86770e0a25a35df3a","https://git.kernel.org/stable/c/5d70eb25b41e9b010828cd12818b06a0c3b04412"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-31533","score":0.00398,"percentile":0.33792,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}