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CVE-2023-34048: VMware vCenter Server Out-of-Bounds Write Vulnerability

CVE-2023-34048 is rated critical with a CVSS v3.1 base score of 9.8 and affects VMware vCenter Server. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2024-01-22, which means exploitation in the wild has been observed.

Vulnerability description

vCenter Server contains an out-of-bounds write vulnerability in the implementation of the DCERPC protocol. A malicious actor with network access to vCenter Server may trigger an out-of-bounds write potentially leading to remote code execution.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-787: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

Affected products

  • VMware vCenter Server: from 4.0 up to and including 5.5; 7.0; 7.0 a; 7.0 b; 7.0 c; 7.0 d; 7.0 update1; 7.0 update1a; 7.0 update1c; 7.0 update1d; 7.0 update2; 7.0 update2a

References