{"id":"CVE-2026-74535","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid deadlocks in iso_sock_timeout\n\niso_sock_timeout() takes lock_sock, so sync disabling the timer while\nholding that lock may deadlock.\n\niso_sock_tim…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid deadlocks in iso_sock_timeout\n\niso_sock_timeout() takes lock_sock, so sync disabling the timer while\nholding that lock may deadlock.\n\niso_sock_tim…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 9"],"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:17:35.917","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74535","references":[{"url":"https://git.kernel.org/stable/c/16d89a63e08280abeef7218970a3bbd7ca62b021","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3c3d5f85db80145636bb991a6005e2760012b985","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/82e982f54f962f72646868ddbb2c3bd9ea178568","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74535.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-74535"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2517050"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74535"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74535"},{"url":"https://kernelcve.org/list/?q=CVE-2026-74535"},{"url":"https://lore.kernel.org/linux-cve-announce/2026081547-CVE-2026-74535-7c9b@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00241,"epssPercentile":0.15218,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:59:30.482999Z"},"scores":{"nvd":8.8,"vendor":4.8,"cna":8.8},"ingestedAt":"2026-10-16T19:46:24.348Z","slug":"CVE-2026-74535","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: avoid deadlocks in iso_sock_timeout\n\niso_sock_timeout() takes lock_sock, so sync disabling the timer while\nholding that lock may deadlock.\n\niso_sock_timeout() may also run concurrently with iso_conn_del(), which\nleads to UAF\n\n        [Task 1]                      [Task hdev->workqueue]\n        iso_sock_timeout              iso_conn_del\n          iso_conn_hold_unless_zero     iso_chan_del\n                           `------------> iso_conn_put\n                                      caller frees hcon\n          iso_conn_put\n            iso_conn_free\n              conn->hcon->iso_data = NULL; /* UAF */\n\nFix the deadlock by removing the disable from the lock_sock sections.\nMove the timer from iso_conn to iso_pinfo to decouple it from iso_conn\nwhich may need to be freed in lock_sock section. Convert some of the\nclear_timer to disable_timer.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74535.json)","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":230410,"id":"CVE-2026-74535","ts":1793134637487,"field":"cvss","old":"4.8","new":"8.8"},{"seq":230409,"id":"CVE-2026-74535","ts":1793134637487,"field":"severity","old":"medium","new":"high"},{"seq":229414,"id":"CVE-2026-74535","ts":1793019748732,"field":"cvss","old":"8.8","new":"4.8"},{"seq":229413,"id":"CVE-2026-74535","ts":1793019748732,"field":"severity","old":"high","new":"medium"}]}