CVE-2026-74540
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix UAF in l2cap_le_connect_rsp l2cap_le_connect_rsp() obtains a channel via __l2cap_get_chan_by_ident() but neither holds a reference nor uses l2cap_chan_hold_unless_zero() before locking and operating on it. A concurrent l2cap_chan_del() triggered by a remote disconnect can free the channel between the lookup and l2cap_chan_lock(), causing a use-after-free. The BR/EDR counterpart l2cap_connect_rsp() and the sibling handler l2cap_le_command_rej() already use l2cap_chan_hold_unless_zero() to safely hold a reference, but l2cap_le_connect_rsp() was left unprotected. Fix by adding l2cap_chan_hold_unless_zero() after the ident lookup and l2cap_chan_put() on the exit path, consistent with other L2CAP response handlers.
Affected versions
Linux kernel versions
3.14
and later are affected. Fixed in
6.6.151,
6.12.103,
6.18.44,
7.1.8,
7.2-rc6
and their respective stable series.
References
5 totalFrequently asked questions
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What is CVE-2026-74540?
CVE-2026-74540 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 3.14 onward and has been patched in 6.6.151, 6.12.103, 6.18.44 and others. CVE-2026-74540 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-74540?
Yes. CVE-2026-74540 has been patched. Fixed versions include 6.6.151, 6.12.103, 6.18.44 and others. If you are running Linux kernel 3.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-74540 actively exploited?
No. CVE-2026-74540 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.