CVE-2023-49933

Vulnerability

SchedMD Slurm versions 22.05.x, 23.02.x, and 23.11.x contain an improper enforcement of message integrity during transmission. This flaw, designated as a protocol message extension vulnerability (CVE-2023-49933), allows an attacker to modify RPC traffic in a way that bypasses the message hash checks intended to detect tampering. The affected versions are all releases in the 22.05, 23.02, and 23.11 series prior to the fixes [1].

Exploitation

An attacker who can intercept or inject network traffic between Slurm daemons can craft malicious RPC messages that bypass the hash verification mechanism. No authentication or user interaction is required beyond network access to the Slurm communication channel [1]. The attack exploits the lack of proper integrity checks, enabling the attacker to replay or alter legitimate RPC requests without detection.

Impact

Successful exploitation allows an attacker to modify RPC traffic, potentially leading to unauthorized actions such as privilege escalation, job manipulation, or denial of service. The detailed impact depends on the specific RPC messages altered, but the core consequence is the compromise of message integrity, which undermines the trust in Slurm's internal communication [1].

Mitigation

SchedMD has released fixed versions 22.05.11, 23.02.7, and 23.11.1 to address this vulnerability. There are no known workarounds; the only mitigation is to upgrade the affected daemons to the patched versions and restart them. This issue was reported by Ryan Hall from Meta Red Team X [1].