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CVE-2020-15069: Sophos XG Firewall Buffer Overflow Vulnerability

CVE-2020-15069 is rated critical with a CVSS v3.1 base score of 9.8 and affects Sophos XG Firewall. 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 2025-02-06, which means exploitation in the wild has been observed.

Vulnerability description

Sophos XG Firewall 17.x through v17.5 MR12 allows a Buffer Overflow and remote code execution via the HTTP/S Bookmarks feature for clientless access. Hotfix HF062020.1 was published for all firewalls running v17.x.

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-120: Buffer Copy without Checking Size of Input

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

Affected products

  • Sophos Xg Firewall Firmware: from 17.0 before 17.5; 17.5; 17.5 maintenance_release1; 17.5 maintenance_release10; 17.5 maintenance_release11; 17.5 maintenance_release12; 17.5 maintenance_release3; 17.5 maintenance_release4; 17.5 maintenance_release5; 17.5 maintenance_release6; 17.5 maintenance_release7; 17.5 maintenance_release8

References