{"id":"CVE-2026-31533","title":"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 …","summary":"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 …","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.15.160, < 5.15.203","linux_kernel >= 6.1.84, < 6.1.169","linux_kernel >= 6.6.18, < 6.6.135","linux_kernel >= 6.7.6, < 6.8","linux_kernel >= 6.8.1, < 6.12.82","linux_kernel >= 6.13, < 6.18.23","linux_kernel >= 6.19, < 6.19.13","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.13"],"published":"2026-04-23","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:19:10.650","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31533","references":[{"url":"https://git.kernel.org/stable/c/02f3ecadb23558bbe068e6504118f1b712d4ece0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/0e43e0a3c94044acc74b8e0927c27972eb5a59e8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2694d408b0e595024e0fc1d64ff9db0358580f74","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/414fc5e5a5aff776c150f1b86770e0a25a35df3a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5d70eb25b41e9b010828cd12818b06a0c3b04412","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a9b8b18364fffce4c451e6f6fd218fa4ab646705","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/aa9facde6c5005205874c37db3fd25799d741baf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00398,"epssPercentile":0.33893,"ingestedAt":"2026-09-08T15:33:26.990Z","ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T15:10:43.493740Z"},"slug":"CVE-2026-31533","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `linux_kernel >= 5.15.160, < 5.15.203`\n- `linux_kernel >= 6.1.84, < 6.1.169`\n- `linux_kernel >= 6.6.18, < 6.6.135`\n- `linux_kernel >= 6.7.6, < 6.8`\n- `linux_kernel >= 6.8.1, < 6.12.82`\n- `linux_kernel >= 6.13, < 6.18.23`\n- `linux_kernel >= 6.19, < 6.19.13`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.13`","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}