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Known exploited · Sophos

CVE-2020-12271: Sophos SFOS SQL Injection Vulnerability

What it is

Sophos Firewall operating system (SFOS) firmware contains a SQL injection vulnerability when configured with either the administration (HTTPS) service or the User Portal is exposed on the WAN zone. Successful exploitation may cause remote code execution to exfiltrate usernames and hashed passwords for the local device admin(s), portal admins, and user accounts used for remote access (but not external Active Directory or LDAP passwords).

Added November 3, 2021Due May 3, 2022CISA KEV catalog 2026.10.01

Vendor
Sophos
Product
SFOS
Added to KEV
November 3, 2021
CISA due date
May 3, 2022
Ransomware use
Known

What CISA requires

Apply updates per vendor instructions.

Forensic triage

No

What to do now

  1. Find every instance of SFOS you run, including the forgotten ones, and check its version against the vendor advisory.
  2. Apply the vendor's fix or mitigation, before May 3, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
  3. Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
  4. Until every instance is patched, block the attack at the edge: a WAF in blocking mode stops SQL injection attempts.

References

CVE-2020-12271 in the National Vulnerability Database

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Block it at the edge while you patch

The Dome's WAF runs the OWASP Core Rule Set in blocking mode and stops SQL injection attempts before they reach your application.

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Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.