CVE-2026-23461 (GCVE-0-2026-23461)
Vulnerability from cvelistv5
Published
2026-04-03 15:15
Modified
2026-10-19 18:35
Severity ?
8.8 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to conn->users. However, l2cap_register_user() and l2cap_unregister_user() don't use conn->lock, creating a race condition where these functions can access conn->users and conn->hchan concurrently with l2cap_conn_del(). This can lead to use-after-free and list corruption bugs, as reported by syzbot. Fix this by changing l2cap_register_user() and l2cap_unregister_user() to use conn->lock instead of hci_dev_lock(), ensuring consistent locking for the l2cap_conn structure.
References
Impacted products
Vendor Product Version
Linux Linux Version: efc30877bd4bc85fefe98d80af60fafc86e5775e
Version: f87271d21dd4ee83857ca11b94e7b4952749bbae
Version: ab4eedb790cae44313759b50fe47da285e2519d5
Version: ab4eedb790cae44313759b50fe47da285e2519d5
Version: ab4eedb790cae44313759b50fe47da285e2519d5
Version: 18ab6b6078fa8191ca30a3065d57bf35d5635761
Version: 6.6.84   ≤
Version: 6.12.20   ≤
Version: 6.13.8   ≤
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