CVE-2020-12271
CVE-2020-12271 is a security flaw in Sophos SFOS. Attackers can run their own code on Sophos SFOS. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 3 Nov 2021, and says ransomware gangs have used it.[1]
Sophos SFOS is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Sophos has published a fix or advice.
Description
CISA calls it an SQL injection in Sophos SFOS. In its words: “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).”[1]
The CVE record adds: “A SQL injection issue was found in SFOS 17.0, 17.1, 17.5, and 18.0 before 2020-04-25 on Sophos XG Firewall devices, as exploited in the wild in April 2020. This affected devices configured with either the administration (HTTPS) service or the User Portal exposed on the WAN zone. A successful attack may have caused remote code execution that exfiltrated 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)”[2]
The underlying weakness is SQL injection (CWE-89), in MITRE’s list of common software weaknesses.
It scores 9.8 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Sophos’s advisory has them[3]. CISA names the product as Sophos SFOS.
Most families won’t have Sophos SFOS; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 3 Nov 2021, 555 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 3 May 2022 to fix it.[1] CISA says ransomware gangs have used it.
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 42%. That’s in the top 2% of the flaws it scores.[4]
CISA assesses it as automatable: attackers can run it against many targets at once.
CISA doesn’t say who was attacked, or how.
Fix
Sophos has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Sophos SFOS is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 3 May 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 9.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks, noting that ransomware gangs have used it.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 42%.[4] |
See also
Other Sophos flaws
- CVE-2020-29574, Sophos CyberoamOS: (CROS) SQL injection ·
- CVE-2020-15069, Sophos XG Firewall: buffer overflow ·
- CVE-2023-1671, Sophos Web Appliance: command injection ·
- CVE-2022-3236, Sophos Firewall: code injection ·
- CVE-2022-1040, Sophos Firewall: authentication bypass ·
Other SQL injection flaws
- CVE-2026-114625, Arista VeloCloud Orchestrator: SQL injection ·
- CVE-2026-76461, Cisco Secure Email Gateway: SQL injection ·
- CVE-2026-9586, Sangoma Switchvox: SQL injection ·
- CVE-2026-72898, Metabase: SQL injection ·
- CVE-2026-60137, WordPress Core: SQL injection ·
Added the same day
- CVE-2021-42258, BQE BillQuick Web Suite: SQL injection ·
- CVE-2021-42013, Apache HTTP Server: path traversal ·
- CVE-2021-41773, Apache HTTP Server: path traversal ·
- CVE-2021-40539, Zoho ManageEngine: aDSelfService plus authentication bypass ·
- CVE-2021-40444, Microsoft MSHTML: remote code execution ·
Every Sophos flaw on CISA’s list · Everything added in November 2021
References
- ^ Cybersecurity and Infrastructure Security Agency. “Sophos SFOS SQL Injection Vulnerability”. Known Exploited Vulnerabilities Catalog, added 3 Nov 2021.
- ^ National Institute of Standards and Technology. “CVE-2020-12271 Detail”. National Vulnerability Database, published 27 Apr 2020.
- ^ Sophos. Advisories and fixes: community.sophos.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.424, percentile 98.7, 31 Oct 2026.
- CVE Program. “CVE-2020-12271”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.