CVE-2026-63976
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: l2cap: clear chan->ident on ECRED reconfiguration success l2cap_ecred_reconf_rsp() returns early on success without clearing chan->ident. Every other L2CAP response handler (l2cap_ecred_conn_rsp, l2cap_le_connect_rsp, l2cap_config_rsp) clears chan->ident after a successful transaction to prevent the channel from matching subsequent responses with the recycled ident value. A remote attacker that completed a reconfiguration as the peer can replay a failure response with the stale ident, causing the kernel to match and destroy the already-established channel via l2cap_chan_del(chan, ECONNRESET). Clear chan->ident for all matching channels on success, and harden the failure path by using l2cap_chan_hold_unless_zero() consistent with other L2CAP handlers (l2cap_le_command_rej, __l2cap_get_chan_by_ident).
Affected versions
Linux kernel versions
5.7
and later are affected. Fixed in
5.10.259,
5.15.210,
6.1.176,
6.6.143,
6.12.93,
6.18.35,
7.0.12,
7.1
and their respective stable series.
References
8 totalFrequently asked questions
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What is CVE-2026-63976?
CVE-2026-63976 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.7 onward and has been patched in 5.10.259, 5.15.210, 6.1.176 and others. CVE-2026-63976 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-2026-63976?
Yes — CVE-2026-63976 has been patched. Fixed versions include 5.10.259, 5.15.210, 6.1.176 and others. If you are running Linux kernel 5.7 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-63976 actively exploited?
No — CVE-2026-63976 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.