CVE-2023-53374 Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early

What is CVE-2023-53374?

CVE-2023-53374 is a high-severity use after free vulnerability in Linux kernel, published on 18 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early

Not calling hci_(dis)connect_cfm before deleting conn referred to by a socket generally results to use-after-free.

When cleaning up SCO connections when the parent ACL is deleted too early, use hci_conn_failed to do the connection cleanup properly.

We also need to clean up ISO connections in a similar situation when connecting has started but LE Create CIS is not yet sent, so do it too here.

Weakness: CWE-416

Which versions are affected by CVE-2023-53374?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53374?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2023-53374 being exploited?

There is no known exploitation of CVE-2023-53374 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-53374, DEBIAN-CVE-2023-53374, GHSA-wwxc-q6v4-r672, UBUNTU-CVE-2023-53374.