CVE-2026-63976

Bluetooth channel teardown via stale L2CAP identifier

Published Jul 19, 2026 · Updated Jul 19, 2026

State-management flaw in Linux Kernel 5.7 through 7.0.11 allows physically proximate attackers to tear down Bluetooth L2CAP channels. l2cap_ecred_reconf_rsp() returns after a successful ECRED reconfiguration without clearing chan->ident, so a replayed failure response matches the live channel and passes it to l2cap_chan_del(). The attacker must establish a Bluetooth Low Energy ACL connection and complete reconfiguration; repeated replays interrupt Bluetooth service, while concurrent teardown can expose a kernel use-after-free.

CVSS severity8.8
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

State-management flaw in Linux Kernel 5.7 through 7.0.11 allows physically proximate attackers to tear down Bluetooth L2CAP channels. l2cap_ecred_reconf_rsp() returns after a successful ECRED reconfiguration without clearing chan->ident, so a replayed failure response matches the live channel and passes it to l2cap_chan_del(). The attacker must establish a Bluetooth Low Energy ACL connection and complete reconfiguration; repeated replays interrupt Bluetooth service, while concurrent teardown can expose a kernel use-after-free.

The record

CVE
CVE-2026-63976
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <00e1950716c6ed67d74777b2db286b0fa23b4be9
  2. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <3b5b5f423b4fd23404a393bda8adba3cd6f74ef1
  3. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
  4. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <8e7977afaef37c6bd2b2654f1bce6ab40d471147
  5. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <ae0152d77d101c920769934fb102b18de0c6f526
  6. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <c2afd2613fda90107c5e2fe8e855627451749c78
  7. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
  8. Affected versionversion=15f02b91056253e8cdc592888f431da0731337b8 <f39049304ba655ffcbb92edbdf8c51a1f1210bed
  9. Affected versionversion=5.7

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=15f02b91056253e8cdc592888f431da0731337b8 <00e1950716c6ed67d74777b2db286b0fa23b4be9; version=15f02b91056253e8cdc592888f431da0731337b8 <3b5b5f423b4fd23404a393bda8adba3cd6f74ef1; version=15f02b91056253e8cdc592888f431da0731337b8 <59f5ecf6ad5c4db6ae81965a96156954a3b0d89a; version=15f02b91056253e8cdc592888f431da0731337b8 <8e7977afaef37c6bd2b2654f1bce6ab40d471147; version=15f02b91056253e8cdc592888f431da0731337b8 <ae0152d77d101c920769934fb102b18de0c6f526; version=15f02b91056253e8cdc592888f431da0731337b8 <c2afd2613fda90107c5e2fe8e855627451749c78; version=15f02b91056253e8cdc592888f431da0731337b8 <cc2b4f749de09975bfa06e58bbbad2f6acd4c79c; version=15f02b91056253e8cdc592888f431da0731337b8 <f39049304ba655ffcbb92edbdf8c51a1f1210bed; version=5.7

Published CVSS scores

8.8Linux kernel CNACVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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