Sophos Web Appliance Command Injection Vulnerability (CVE-2023-1671)
Sophos Web Appliance contains a command injection vulnerability in the warn-proceed handler that allows for remote code execution.
A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2023-12-07 under CISA BOD 22-01.
This is a Command Injection (CWE-77) vulnerability in Sophos Web Appliance. 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. Exploitation requires remote network access, low attack complexity, no authentication required, and no user interaction required.
📧
Phishing link
🖼
Malicious file
🔓
Server compromised
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/172016/Sophos-Web-Appliance-4.3.10.4-Command-Injection.html
Get the fix
Apply the fixed package from your vendor. The advisory lists affected versions and the exact fixed build.
↗ Vendor advisoryManual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
References
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References
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