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Vulnerabilities

Vulnerability · CVE-2026-53256

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans…

Published Jun 25, 2026 · catalog updated Oct 15, 2026 · linux kernel

Check if you run it

No confirmed exploitation is on record for CVE-2026-53256. EPSS is 0.26%. Act only if a listed version of linux kernel is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High8.0
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.26%
Remediation
Advisory link
Affected products
cpe linux/linux kernel

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a reference. rfcomm_connect_ind() then locks the listener, queues a child socket on it, and may notify it after unlocking it. The buggy scenario involves two paths, with each column showing the order within that path: rfcomm_connect_ind(): listener close: 1. Find parent in 1. close() enters rfcomm_get_sock_by_channel() rfcomm_sock_release(). 2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown() without pinning parent. closes the listener. 3. Call lock_sock(parent) and 3. rfcomm_sock_kill() bt_accept_enqueue(parent, unlinks and puts parent. sk, true). 4. Read parent flags and may 4. parent can be freed. call sk_state_change(). If close wins the race, parent can be freed before rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the deferred-setup callback. Take a reference on the listener before leaving rfcomm_sk_list.lock. After lock_sock() succeeds, recheck that it is still in BT_LISTEN before queueing a child, cache the deferred-setup bit while the parent is locked, and drop the reference after the last parent use. KASAN reported a slab-use-after-free in lock_sock_nested() from rfcomm_connect_ind(), with the freeing stack going through rfcomm_sock_kill() and rfcomm_sock_release().

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe linux/linux kernel2.6.12

How to fix CVE-2026-53256

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-53256. EPSS is 0.26%. Act only if a listed version of linux kernel is installed.

Which versions are affected?

Compare what you have installed with linux/linux kernel 2.6.12. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-416: Use After Free. EPSS 0.26%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 25, 2026 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a reference. rfcomm_connect_ind() then locks the listener, queues a child socket on it, and may notify it after unlocking i

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a reference. rfcomm_connect_ind() then locks the listener, queues a child socket on it, and may notify it after unlocking i

Sources

  • CVE.orgVulnerability recordCVE-2026-53256

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-53256

    30-day exploitation probability 0.3%

    first.org
  • NIST NVDVulnerability recordCVE-2026-53256

    In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that lock without taking a

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.