CVE-2026-44235

A flaw was found in rabbitmq-c, a C-language AMQP (Advanced Message Queuing Protocol) client library. A malicious AMQP server or an on-path attacker can send an undersized HEADER or METHOD frame during client login, leading to an unsigned size_t underflow. This underflow causes an out-of-bounds read, which can result in a process crash and a denial of service (DoS).

This Moderate impact denial of service vulnerability in rabbitmq-c affects Red Hat products that utilize the library to connect to AMQP servers. An attacker, either a malicious server or an on-path adversary, can send a crafted AMQP frame during client login, leading to an out-of-bounds read and a client process crash. Exploitation requires either a compromised server or an unprotected network path, and does not result in information disclosure or arbitrary code execution.

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.

To mitigate this issue, ensure that all AMQP client connections are configured to use TLS with certificate validation. This prevents on-path attackers from exploiting the vulnerability by ensuring the authenticity of the AMQP server and encrypting traffic. Proper certificate management and configuration are required on both the client and server sides. Restart any services utilizing rabbitmq-c after applying this configuration change for it to take effect.