---
title: "CVE-2023-1671: Sophos Web Appliance Command Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2023-1671/
description: "CVE-2023-1671 (Sophos Web Appliance): Exploited in the wild (CISA KEV). A pre-auth command injection vulnerability in the warn-proceed handler of Sophos Web…"
type: vulnerability-record
section: "Security Digest"
date_published: 2023-04-04
date_modified: 2025-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2023-1671"
kev: true
cvss: 9.8
epss: 0.99999
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2023-1671: Sophos Web Appliance Command Injection Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Sophos Web Appliance. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2023-11-16, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2023-12-07 ; treat that as the outer limit, not the target.
- EPSS 100.0% , percentile 100.0: FIRST’s model estimates a 100.0% chance of exploitation activity in the next 30 days, higher than 100.0% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

## What it is

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.

## Affected products (CVE record)

- Sophos Sophos Web Appliance: unspecified < 4.3.10.4

## Severity

- Sophos CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2023-11-16; federal due date 2023-12-07. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 100.00% probability of exploitation activity in the next 30 days; percentile 100.0.

## Sources

- [Listed in CISA KEV notes (sophos.com)](https://www.sophos.com/en-us/security-advisories/sophos-sa-20230404-swa-rce)
- [CVE.org record CVE-2023-1671](https://www.cve.org/CVERecord?id=CVE-2023-1671)
- [NVD entry CVE-2023-1671](https://nvd.nist.gov/vuln/detail/CVE-2023-1671)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-1671)
- [packetstormsecurity.com](http://packetstormsecurity.com/files/172016/Sophos-Web-Appliance-4.3.10.4-Command-Injection.html)

---
Source page: https://erroneo.us/security/cve/CVE-2023-1671/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt