CVE-2022-34412

Vulnerability

Dell PowerEdge BIOS and Dell Precision BIOS contain an Improper SMM (System Management Mode) communication buffer verification vulnerability (CVE-2022-34412). The flaw exists in the SMM communication buffer handling code, allowing improper validation of buffer contents. This affects multiple Dell PowerEdge server and Dell Precision workstation BIOS versions, as identified in Dell advisory DSA-2022-204 [1].

Exploitation

An attacker must have local access to the system and possess high privileges (such as Administrator or root-level access) to execute the exploit. The attack complexity is high, requiring precise manipulation of SMM communication buffers via System Management Interrupts (SMIs). The attacker needs to craft specific inputs to trigger the buffer verification flaw, then leverage it to execute code within SMM or cause a denial of service [1].

Impact

Successful exploitation results in arbitrary code execution within SMM (System Management Mode) or denial of service. Since SMM operates at the highest privilege level (ring -2), an attacker can gain full control of the system firmware, potentially bypassing operating system security mechanisms. The CVSS vector string is CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H with a base score of 7.5, indicating high impact on confidentiality, integrity, and availability within the compromised scope [1].

Mitigation

Dell released firmware updates to address this vulnerability. Users should update their BIOS/UEFI firmware to the versions specified in DSA-2022-204 [1]. No workarounds are provided; applying the latest BIOS update from Dell's support site is the recommended mitigation.