CVE-2023-53827

Code execution via L2CAP channel use-after-free

Published Dec 9, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel L2CAP allows physically proximate attackers to execute code through crafted Bluetooth disconnect traffic. The l2cap_disconnect_req and l2cap_disconnect_rsp handlers can acquire a reference after the channel count reaches zero, leaving teardown code to access a freed channel. An unauthenticated, unpaired device within Bluetooth range can disclose kernel heap data, corrupt kernel state, hijack control flow, or panic the host when Bluetooth is enabled.

CVSS severity8.8
High
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel L2CAP allows physically proximate attackers to execute code through crafted Bluetooth disconnect traffic. The l2cap_disconnect_req and l2cap_disconnect_rsp handlers can acquire a reference after the channel count reaches zero, leaving teardown code to access a freed channel. An unauthenticated, unpaired device within Bluetooth range can disclose kernel heap data, corrupt kernel state, hijack control flow, or panic the host when Bluetooth is enabled.

The record

CVE
CVE-2023-53827
Published
Dec 9, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1210
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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=3.5
  2. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <1351551aa9058e07a20a27a158270cf84fcde621
  3. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <348d446762e7c70778df8bafbdf3fa0df2123f58
  4. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <a2a9339e1c9deb7e1e079e12e27a0265aea8421a
  5. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <ac6725a634f7e8c0330610a8527f20c730b61115
  6. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <c02421992505c95c7f3c9ad59ee35e22eac60988
  7. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <d82a439c3cfdb28aa7e82e2e849c5c4dd9fca284
  8. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <d9ba36c22a7bb09d6bac4cc2f243eff05da53f43
  9. Affected versionversion=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <f2d38e77aa5f3effc143e7dd24da8acf02925958

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3.5; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <1351551aa9058e07a20a27a158270cf84fcde621; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <348d446762e7c70778df8bafbdf3fa0df2123f58; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <a2a9339e1c9deb7e1e079e12e27a0265aea8421a; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <ac6725a634f7e8c0330610a8527f20c730b61115; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <c02421992505c95c7f3c9ad59ee35e22eac60988; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <d82a439c3cfdb28aa7e82e2e849c5c4dd9fca284; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <d9ba36c22a7bb09d6bac4cc2f243eff05da53f43; version=61d6ef3e3408cdf7e622646fb90a9f7f9560b943 <f2d38e77aa5f3effc143e7dd24da8acf02925958

Published CVSS scores

8.8Linux kernel CVE teamCVSS: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

T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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