CVE-2022-34422

Vulnerability

An improper SMM (System Management Mode) communication buffer verification vulnerability exists in Dell PowerEdge BIOS and Dell Precision BIOS. The bug resides in the SMM communication buffer handling code, where insufficient validation of buffer contents can be triggered by a local attacker with high privileges. Affected versions include multiple BIOS releases for PowerEdge and Precision systems; the exact version list is provided in the Dell advisory [1].

Exploitation

To exploit this vulnerability, an attacker must have local access to the system and possess high privileges (e.g., Administrator or root). The attacker can craft a malicious SMI (System Management Interrupt) that leverages the improper buffer verification to corrupt SMM memory or execute arbitrary code. No user interaction is required beyond the initial privilege escalation to high privileges.

Impact

Successful exploitation allows the attacker to execute arbitrary code within SMM, which operates at the highest privilege level (ring -2). This can lead to full compromise of the system's firmware, enabling persistent control, data exfiltration, or denial of service. The CVSS v3.1 base score for this vulnerability is 7.5 (High) with vector AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H [1].

Mitigation

Dell has released a firmware update as part of DSA-2022-204 to address this vulnerability [1]. Users should update their PowerEdge or Precision BIOS to the latest version provided by Dell. No workarounds are available; applying the patch is the only mitigation. The vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog as of the publication date.