Bluetooth: l2cap: clear chan->ident on ECRED reconfiguration success
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
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).
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) 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
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-63976
- 2026-10-03 Alias added: GHSA-2c97-7qvf-wx4v
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
- 2026-10-19 Weakness changed · CISA ADP
- 2026-10-31 CVSS score changed · Red Hat
- 2026-10-31 Affected versions changed · Red Hat
References
Other 8
- https://git.kernel.org/stable/c/59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
- https://git.kernel.org/stable/c/ae0152d77d101c920769934fb102b18de0c6f526
- https://git.kernel.org/stable/c/c2afd2613fda90107c5e2fe8e855627451749c78
- https://git.kernel.org/stable/c/cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
- https://git.kernel.org/stable/c/3b5b5f423b4fd23404a393bda8adba3cd6f74ef1
- https://git.kernel.org/stable/c/f39049304ba655ffcbb92edbdf8c51a1f1210bed
- https://git.kernel.org/stable/c/8e7977afaef37c6bd2b2654f1bce6ab40d471147
- https://git.kernel.org/stable/c/00e1950716c6ed67d74777b2db286b0fa23b4be9
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Sources
- CVE-2026-63976 · CVE Program
- CVE-2026-63976 · NVD
- FIRST EPSS
- GHSA-2c97-7qvf-wx4v · GitHub Advisory Database · CC BY 4.0
- CVE-2026-63976 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences