CVE-2023-1671 Sophos Web Appliance Command Injection

Exploited in the wild Critical 9.8 Published 4 Apr 2023 Updated 21 Oct 2025

Attackers can execute arbitrary code on Sophos Web Appliance via a pre-auth command injection in the warn-proceed handler.

Exploited in the wild: Since 16 Nov 2023
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2023-1671?

CVE-2023-1671 is a critical command injection vulnerability in Sophos Web Appliance, published on 4 Apr 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-77

Which versions are affected by CVE-2023-1671?

It affects 1 product.

Products include Sophos Web Appliance.

How do I fix CVE-2023-1671?

No fix has been published for CVE-2023-1671 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 7 Dec 2023.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2023-1671 being exploited?

Yes. Attackers have exploited CVE-2023-1671 in the wild since at least 16 Nov 2023.

Public exploit code: 1 Exploit-DB entry, 1 Nuclei template and 3 proofs of concept on GitHub.

Sources

Also known as GHSA-5f37-m2hf-qphr.