CVE-2026-31512
kernel: Bluetooth: L2CAP: Validate PDU length before reading SDU length in l2cap_ecred_data_rcv()
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · April 22, 2026
Updated · June 28, 2026
Description
A flaw was found in the Linux kernel's Bluetooth L2CAP (Logical Link Control and Adaptation Protocol) component. The l2cap_ecred_data_rcv() function fails to validate the incoming data packet unit (PDU) length before attempting to read the Service Data Unit (SDU) length. This oversight allows an attacker to craft a malicious packet that, when processed, can cause the system to read beyond the allocated buffer, potentially leading to information disclosure or a denial of service.
Statement
Upstream mirrors the ERTM pskb_may_pull() guard before reading SDU length on the enhanced credit-based data path. Red Hat treats this as a remote-adjacent Bluetooth parser hardening issue. Consume patched kernels; unload bluetooth where acceptable.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
To mitigate this issue, prevent the bluetooth module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.
CVSS / CWE
CVSS 3.1 · 5.7CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
CWE-1284 · Improper Validation of Specified Quantity in Input