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VulnerabilityPublished

CVE-2026-63976: Linux kernel · Bluetooth: l2cap: clear chan->ident on ECRED reconfiguration success

Source GCVE Database

0
Authoritative record:CVE-2026-63976· High 8.8

Not known to be exploited · CVSS 8.8 High · fixed in f39049304ba655ffcbb92edbdf8c51a1f1210bed : patch Linux kernel soon.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score
8.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in f39049304ba655ffcbb92edbdf8c51a1f1210bed, cc2b4f749de09975bfa06e58bbbad2f6acd4c79c, c2afd2613fda90107c5e2fe8e855627451749c78 +5
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 19 Jul 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < f39049304ba655ffcbb92edbdf8c51a1f1210bed
Fixed in
  • f39049304ba655ffcbb92edbdf8c51a1f1210bed
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
Fixed in
  • cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < c2afd2613fda90107c5e2fe8e855627451749c78
Fixed in
  • c2afd2613fda90107c5e2fe8e855627451749c78
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < ae0152d77d101c920769934fb102b18de0c6f526
Fixed in
  • ae0152d77d101c920769934fb102b18de0c6f526
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < 59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
Fixed in
  • 59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
LinuxLinuxAffected
  • ≥ 15f02b91056253e8cdc592888f431da0731337b8, < 8e7977afaef37c6bd2b2654f1bce6ab40d471147
Fixed in
  • 8e7977afaef37c6bd2b2654f1bce6ab40d471147

AI-suggested

A fix has been implemented in the Linux kernel to clear chan->ident on successful ECRED reconfiguration and to harden the failure handling path. Users should apply the official Linux kernel updates that include this patch. Since this is a kernel-level vulnerability, updating to a patched kernel version is the recommended remediation. Patch status is not explicitly confirmed in the provided data; users should consult the Linux kernel vendor advisory for current patch availability and guidance.

Description

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).

References

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