Linux Kernel up to 6.2.11 Bluetooth l2cap_disconnect_req/l2cap_disconnect_rsp use after free

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.2.11. This vulnerability affects the function l2cap_disconnect_req/l2cap_disconnect_rsp of the component Bluetooth. This manipulation causes use after free. This vulnerability is registered as CVE-2023-53827. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.2.11 and classified as critical. Affected by this vulnerability is the function l2cap_disconnect_req/l2cap_disconnect_rsp of the component Bluetooth. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp} Similar to commit d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put"), just use l2cap_chan_hold_unless_zero to prevent referencing a channel that is about to be destroyed.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2023-53827 since 12/09/2025. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/30/2026).

The vulnerability scanner Nessus provides a plugin with the ID 300005 (RHEL 8 : kernel (RHSA-2026:3388)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.313, 4.19.281, 5.4.241, 5.10.178, 5.15.108, 6.1.25 or 6.2.12 eliminates this vulnerability. Applying the patch f2d38e77aa5f3effc143e7dd24da8acf02925958/1351551aa9058e07a20a27a158270cf84fcde621/c02421992505c95c7f3c9ad59ee35e22eac60988/d9ba36c22a7bb09d6bac4cc2f243eff05da53f43/ac6725a634f7e8c0330610a8527f20c730b61115/348d446762e7c70778df8bafbdf3fa0df2123f58/d82a439c3cfdb28aa7e82e2e849c5c4dd9fca284/a2a9339e1c9deb7e1e079e12e27a0265aea8421a is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (300005) and CERT Bund (WID-SEC-2025-2765). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.312
• 4.19.280
• 5.4.240
• 5.10.177
• 5.15.107
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 6.2.9
• 6.2.10
• 6.2.11

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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