{"id":"CVE-2026-23240","title":"tls: Fix race condition in tls_sw_cancel_work_tx()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ntls: Fix race condition in tls_sw_cancel_work_tx()\n\nThis issue was discovered during a code audit.\n\nAfter cancel_delayed_work_sync() is called from tls_sk_proto_close()…","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","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < a5de36d6cee74a92c1a21b260bc507e64bc451de","Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 854cd32bc74fe573353095e90958490e4e4d641b","Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 17153f154f80be2b47ebf52840f2d8f724eb2f3b","Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 7bb09315f93dce6acc54bf59e5a95ba7365c2be4","Linux 5.3"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T15:06:53.340021Z"},"published":"2026-03-10","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:09:50.834Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23240","references":[{"url":"https://git.kernel.org/stable/c/a5de36d6cee74a92c1a21b260bc507e64bc451de"},{"url":"https://git.kernel.org/stable/c/854cd32bc74fe573353095e90958490e4e4d641b"},{"url":"https://git.kernel.org/stable/c/17153f154f80be2b47ebf52840f2d8f724eb2f3b"},{"url":"https://git.kernel.org/stable/c/7bb09315f93dce6acc54bf59e5a95ba7365c2be4"}],"tags":["cve.org"],"epss":0.00509,"epssPercentile":0.42139,"ingestedAt":"2026-10-16T17:24:46.642Z","slug":"CVE-2026-23240","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ntls: Fix race condition in tls_sw_cancel_work_tx()\n\nThis issue was discovered during a code audit.\n\nAfter cancel_delayed_work_sync() is called from tls_sk_proto_close(),\ntx_work_handler() can still be scheduled from paths such as the\nDelayed ACK handler or ksoftirqd.\nAs a result, the tx_work_handler() worker may dereference a freed\nTLS object.\n\nThe following is a simple race scenario:\n\n          cpu0                         cpu1\n\ntls_sk_proto_close()\n  tls_sw_cancel_work_tx()\n                                 tls_write_space()\n                                   tls_sw_write_space()\n                                     if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))\n    set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);\n    cancel_delayed_work_sync(&ctx->tx_work.work);\n                                     schedule_delayed_work(&tx_ctx->tx_work.work, 0);\n\nTo prevent this race condition, cancel_delayed_work_sync() is\nreplaced with disable_delayed_work_sync().\n\n## Affected\n\n- `Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < a5de36d6cee74a92c1a21b260bc507e64bc451de`\n- `Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 854cd32bc74fe573353095e90958490e4e4d641b`\n- `Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 17153f154f80be2b47ebf52840f2d8f724eb2f3b`\n- `Linux >= f87e62d45e51b12d48d2cb46b5cde8f83b866bc4 < 7bb09315f93dce6acc54bf59e5a95ba7365c2be4`\n- `Linux 5.3`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}