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Review reviewHigh

CVE-2026-64557

Linux

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb() l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after release_sock(parent). Once the parent lock is dropped the newly enqueued child socket sk is reachable via the accept queue, so another task can accept and free it before the callback dereferences sk, resulting in a use-after-free. Rework the ->new_connection() op so the core, rather than the callback, owns the child channel's lifetime. The op now receives a pre-allocated new_chan and return...

CVSS
8.8
EPSS
-
- percentile
CISA KEV
Not listed
Published
2026.07.29
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 8.8

Vulnerability overview

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb() l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after release_sock(parent). Once the parent lock is dropped the newly enqueued child socket sk is reachable via the accept queue, so another task can accept and free it before the callback dereferences sk, resulting in a use-after-free. Rework the ->new_connection() op so the core, rather than the callback, owns the child channel's lifetime. The op now receives a pre-allocated new_chan and return...

Affected product and versions

Product
Linux
Affected versions
>= 8ffb929098a56939ac71509302eeab5b207bf262 < b39298044e5534612511a2ff5de03ba5f6e7a820, >= 8ffb929098a56939ac71509302eeab5b207bf262 < 8c37e4338c801ebb8cee52436c01c41e009f6e87, >= 8ffb929098a56939ac71509302eeab5b207bf262 < 84e718b6a814edc84159361f9f454a4e92ae91ae, >= 8ffb929098a56939ac71509302eeab5b207bf262 < 36da806f7fbaee56ad9e81859deec203f9728700, >= 8ffb929098a56939ac71509302eeab5b207bf262 < 733e76e74e406c1d1ddc7369420dd8a47f48bb8a, >= 8ffb929098a56939ac71509302eeab5b207bf262 < 6fef032af0092ed5ccb767239a9ac1bc38c08a40, >= 3.13
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Not available
CVE-2026-64557 — Linux | SECUFOCUS NOW