CVE-2026-63976
Linux Bluetooth L2CAP ident reuse allows replayed responses to reset channels
Is CVE-2026-63976 being exploited?
Not confirmed. CVE-2026-63976 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.46% probability of exploitation in the next 30 days.
How severe is CVE-2026-63976?
CVE-2026-63976 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-63976?
Yes. A fix has been recorded for CVE-2026-63976. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-63976 affect?
CVE-2026-63976 affects Linux kernel (Bluetooth L2CAP subsystem). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-63976?
Apply Linux kernel update containing the L2CAP fix and restart Bluetooth services.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can replay stale L2CAP responses to match and delete established Bluetooth channels, causing connection reset and denial of service.
Patch when possible
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < 59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < ae0152d77d101c920769934fb102b18de0c6f526
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < c2afd2613fda90107c5e2fe8e855627451749c78
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < 3b5b5f423b4fd23404a393bda8adba3cd6f74ef1
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < f39049304ba655ffcbb92edbdf8c51a1f1210bed
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < 8e7977afaef37c6bd2b2654f1bce6ab40d471147
- affected>= 15f02b91056253e8cdc592888f431da0731337b8 and < 00e1950716c6ed67d74777b2db286b0fa23b4be9
- affected5.7
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.