// CVE

CVE-2023-1671

Critical 9.8
9.8CVSS
100%EPSS
—CISA KEV

Summary

A pre-auth command injection vulnerability in the warn-proceed handler of Sophos Web Appliance older than version 4.3.10.4 allows execution of arbitrary code.

Published: 2023-04-04

Analysis

🟠 High — imminent exploitation

Weakness: Command Injection (CWE-77). Runs commands via unsanitized input.

How it's exploited: Exploitable over the network (internet-reachable), unauthenticated, no user interaction, and with low complexity.

⚠️ Critical combo: remote, unauthenticated and no interaction → trivial to automate.

Impact: Full compromise (confidentiality, integrity and availability).

Status: Exploit probability (EPSS, 30 days): 100% — high.

How to defend:
  • Apply the vendor patch according to risk priority.
  • Reduce exposure: keep it off the internet; firewall, VPN or network segmentation.
  • Detect: turn this CVE into detection rules.

MITRE ATT&CK technique: T1190 · Exploit Public-Facing Application · T1059 · Command and Scripting Interpreter

Practice it in the arsenal: WAF Bypass · PowerShell Decoder · Reverse Shells

CVSS vector

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

The vector encodes how it's exploited (translated above, in the analysis). Break it down in the CVSS tool →

← Back to the Threat Radar

Sources: CISA KEV · EPSS · FIRST.org · NVD. Analysis derived from the CVSS vector and exploitation status (no AI). Informational; always verify against the vendor's official advisory.