CVE-2026-43134 Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ
Attackers can bypass Bluetooth encryption key size requirements, potentially weakening security for nearby devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43134?
CVE-2026-43134 is a high-severity vulnerability in Linux kernel, published on 6 May 2026. 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: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ
This adds a check for encryption key size upon receiving L2CAP_LE_CONN_REQ which is required by L2CAP/LE/CFC/BV-15-C which expects L2CAP_CR_LE_BAD_KEY_SIZE.
Weakness: CWE-326
Which versions are affected by CVE-2026-43134?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43134?
Apply the vendor's patch.
Is CVE-2026-43134 being exploited?
There is no known exploitation of CVE-2026-43134 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43134, DEBIAN-CVE-2026-43134, GHSA-jc53-6rw8-5w3x, ROOT-OS-DEBIAN-11-CVE-2026-43134, ROOT-OS-UBUNTU-2204-CVE-2026-43134, ROOT-OS-UBUNTU-2404-CVE-2026-43134 and 1 more.