{"id":"CVE-2026-90256","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind\n\nhci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via\nhci_conn_timeout (disc…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind\n\nhci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via\nhci_conn_timeout (disc…","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","vendor":"Linux","product":"Linux","affected":["Linux >= ab4eedb790cae44313759b50fe47da285e2519d5 < b495a3a9b33bc4e4613e685bf5c96c136caa22d8","Linux >= ab4eedb790cae44313759b50fe47da285e2519d5 < 2b66c83ff1751d6bd3201b3017206262ab46dc05","Linux efc30877bd4bc85fefe98d80af60fafc86e5775e","Linux f87271d21dd4ee83857ca11b94e7b4952749bbae","Linux 18ab6b6078fa8191ca30a3065d57bf35d5635761","Linux >= 6.6.84 < 6.7","Linux >= 6.12.20 < 6.13","Linux >= 6.13.8 < 6.14","Linux 6.14"],"published":"2026-09-17","updated":"2026-09-18","sourceUpdated":"2026-09-18T18:17:51.170","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90256","references":[{"url":"https://git.kernel.org/stable/c/2b66c83ff1751d6bd3201b3017206262ab46dc05","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b495a3a9b33bc4e4613e685bf5c96c136caa22d8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/0fa448369c87e20b2aeaeaca0187d698dd61f791"},{"url":"https://git.kernel.org/stable/c/7c032b6d48a46634cbd58aaebad2638c00ad3b51"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90256.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-90256"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2536720"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90256"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90256"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90256.mbox"},{"url":"https://kernelcve.org/list/?q=CVE-2026-90256"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00379,"epssPercentile":0.31742,"ingestedAt":"2026-09-17T16:21:47.842Z","cwe":["CWE-416"],"scores":{"nvd":8.8,"vendor":5.9},"slug":"CVE-2026-90256","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind\n\nhci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via\nhci_conn_timeout (disc_work) -> hci_proto_disconn_ind ->\nl2cap_disconn_ind.  This is UAF if the l2cap_conn is deleted\nconcurrently.\n\ndisc_work is disabled sync in hci_conn_del(), so we cannot take\nhci_dev_lock in disc_work.\n\nFix by using proto_lock to guard l2cap_data, in addition to hdev->lock\nwhich is held in other access paths.\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, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90256.json)","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":207219,"id":"CVE-2026-90256","ts":1789757339709,"field":"cvss","old":null,"new":"8.8"},{"seq":207218,"id":"CVE-2026-90256","ts":1789757339709,"field":"severity","old":"none","new":"high"}]}