IM
IronMonkey Threat Research

CVE-2026-53256 HIGH

Published: 2026-06-25 | Last Modified: 2026-07-08 | Status: Analyzed

Description

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().

CVSS Metrics

Base Score: 8.0 (HIGH)

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack VectorADJACENT_NETWORK
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactHIGH
Integrity ImpactHIGH
Availability ImpactHIGH

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Type: Secondary

Exploitability Score: 2.1

Impact Score: 5.9

Weaknesses

Source Type Description
[email protected] Primary
en CWE-416

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7fd341257200> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd2a149e280> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd39c4df6c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd2a149e480> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd341256ac0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd341255a80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd34bb9d600> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd3106f2600> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd384a276c0> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd341257000> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd384a26cc0> Operating System
linux linux_kernel 2.6.12 <built-in method update of dict object at 0x7fd2d8259d80> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd2d8258a80> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd34011fcc0> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd360274f80> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd2d8259c40> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd360277780> Operating System
linux linux_kernel 7.1 <built-in method update of dict object at 0x7fd341255280> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*

References