CVE-2023-1671
Sophos Web Appliance Command Injection Vulnerability
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 status
CISA Known Exploited Vulnerabilities
Listed by CISA on 16 November 2023. US federal agencies were required to remediate it by 7 December 2023.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 100%, which is higher than 99.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2023-1671 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2023-1671.
What does CVE-2023-1671 affect?
CVE-2023-1671 affects 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.
How severe is CVE-2023-1671?
CVE-2023-1671 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 100%, higher than 99.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 7 December 2023.
How should organisations respond to CVE-2023-1671?
Apply the vendor patch for Sophos Web Appliance as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.