{"api_version":"1","generated_at":"2026-08-17T11:24:49+00:00","cve":"CVE-2026-74535","urls":{"html":"https://cve.report/CVE-2026-74535","api":"https://cve.report/api/cve/CVE-2026-74535.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74535","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74535"},"summary":{"title":"Bluetooth: ISO: avoid deadlocks in iso_sock_timeout","description":"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_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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-15 13:17:58","updated_at":"2026-08-17 06:19:50"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/3c3d5f85db80145636bb991a6005e2760012b985","name":"https://git.kernel.org/stable/c/3c3d5f85db80145636bb991a6005e2760012b985","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/16d89a63e08280abeef7218970a3bbd7ca62b021","name":"https://git.kernel.org/stable/c/16d89a63e08280abeef7218970a3bbd7ca62b021","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43","name":"https://git.kernel.org/stable/c/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/82e982f54f962f72646868ddbb2c3bd9ea178568","name":"https://git.kernel.org/stable/c/82e982f54f962f72646868ddbb2c3bd9ea178568","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74535","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74535","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a58d0f5dac322e16cc75334d000666512341bde5 16d89a63e08280abeef7218970a3bbd7ca62b021 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected dc26097bdb864a0d5955b9a25e43376ffc1af99b 82e982f54f962f72646868ddbb2c3bd9ea178568 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected dc26097bdb864a0d5955b9a25e43376ffc1af99b 3c3d5f85db80145636bb991a6005e2760012b985 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected dc26097bdb864a0d5955b9a25e43376ffc1af99b 200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f53e7489273dc2bb307bf50f319b3762d45534f0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.2 6.12.103 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.11.11 6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.13","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.103 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.44 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.8 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"74535","cve":"CVE-2026-74535","epss":"0.001680000","percentile":"0.064930000","score_date":"2026-08-16","updated_at":"2026-08-17 00:01:04"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/bluetooth/iso.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"16d89a63e08280abeef7218970a3bbd7ca62b021","status":"affected","version":"a58d0f5dac322e16cc75334d000666512341bde5","versionType":"git"},{"lessThan":"82e982f54f962f72646868ddbb2c3bd9ea178568","status":"affected","version":"dc26097bdb864a0d5955b9a25e43376ffc1af99b","versionType":"git"},{"lessThan":"3c3d5f85db80145636bb991a6005e2760012b985","status":"affected","version":"dc26097bdb864a0d5955b9a25e43376ffc1af99b","versionType":"git"},{"lessThan":"200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43","status":"affected","version":"dc26097bdb864a0d5955b9a25e43376ffc1af99b","versionType":"git"},{"status":"affected","version":"f53e7489273dc2bb307bf50f319b3762d45534f0","versionType":"git"},{"lessThan":"6.12.103","status":"affected","version":"6.12.2","versionType":"semver"},{"lessThan":"6.12","status":"affected","version":"6.11.11","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/bluetooth/iso.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.13"},{"lessThan":"6.13","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.103","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.44","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.103","versionStartIncluding":"6.12.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.44","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.8","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11.11","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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_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."}],"metrics":[{"cvssV3_1":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:A - The bug is in the Bluetooth ISO socket layer (BTPROTO_ISO); iso_sock_timeout and iso_conn_del are reached via HCI disconnect/connect events from an adjacent BLE peer and local ISO socket syscalls, which per kernel guidance is Adjacent not Network.\nAC:L - Exploitation is a race between iso_sock_timeout and iso_conn_del that an attacker can reliably force by controlling ISO connect/disconnect timing and socket send timeouts (SO_SNDTIMEO) on concurrent workqueues, so success does not depend on uncontrollable conditions.\nPR:N - An adjacent Bluetooth attacker can trigger iso_conn_del through remote HCI disconnect/failure events without any credentials or privileges on the victim host; only a normal active or pending ISO/LE Audio session must exist on the target.\nUI:N - No deliberate victim interaction beyond routine Bluetooth/LE Audio operation is required; exploitation can occur in the background while an ISO connection is pending or active, without opening files or performing a separate enabling action.\nS:U - The UAF/deadlock corrupts kernel heap memory on the host and enables local privilege escalation within the kernel security boundary, not a cross-boundary escape such as VM guest-to-host or IOMMU bypass.\nC:H - iso_conn_free dereferences conn->hcon after concurrent iso_conn_del frees the hci_conn (UAF on conn->hcon->iso_data), enabling arbitrary kernel memory read/disclosure through heap corruption per UAF guidance.\nI:H - The UAF permits writes through conn->hcon->iso_data and hci_conn_drop on freed hci_conn memory, providing heap corruption primitives that can be leveraged for arbitrary kernel writes or code execution.\nA:H - The UAF causes kernel oops/panic on freed hci_conn access, and the lock_sock versus disable_delayed_work_sync deadlock in iso_sock_timeout/iso_conn_del paths can hang the system; both crash and deadlock map to High availability impact."}]}],"providerMetadata":{"dateUpdated":"2026-08-17T05:48:24.441Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/16d89a63e08280abeef7218970a3bbd7ca62b021"},{"url":"https://git.kernel.org/stable/c/82e982f54f962f72646868ddbb2c3bd9ea178568"},{"url":"https://git.kernel.org/stable/c/3c3d5f85db80145636bb991a6005e2760012b985"},{"url":"https://git.kernel.org/stable/c/200fa1629c57a3ca2b03d3ca63fd3a9bfd910c43"}],"title":"Bluetooth: ISO: avoid deadlocks in iso_sock_timeout","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74535","datePublished":"2026-08-15T12:27:48.449Z","dateReserved":"2026-08-15T05:44:03.913Z","dateUpdated":"2026-08-17T05:48:24.441Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-15 13:17:58","lastModifiedDate":"2026-08-17 06:19:50","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"ADJACENT_NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74535","Ordinal":"1","Title":"Bluetooth: ISO: avoid deadlocks in iso_sock_timeout","CVE":"CVE-2026-74535","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74535","Ordinal":"1","NoteData":"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_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.","Type":"Description","Title":"Bluetooth: ISO: avoid deadlocks in iso_sock_timeout"}]}}}