CVE-2022-3236

From Exploited flaws, HARD’s guide to the flaws being used in attacks · Checked
This article is about a flaw in Sophos Firewall. For every flaw being used in attacks, see Exploited flaws; for Sophos’s, see Sophos flaws being used in attacks.

CVE-2022-3236 is a security flaw in Sophos Firewall. Attackers can run their own code on Sophos Firewall. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 23 Sep 2022.[1]

Sophos Firewall 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 a code injection in Sophos Firewall. In its words: “A code injection vulnerability in the User Portal and Webadmin of Sophos Firewall allows for remote code execution.”[1]

The underlying weakness is code injection (CWE-94), in MITRE’s list of common software weaknesses.[2]

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 Firewall.

Most families won’t have Sophos Firewall; it’s for whoever looks after IT at work.

Exploitation

CISA added it to its catalog of known exploited vulnerabilities on 23 Sep 2022, within a day of it being made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 14 Oct 2022 to fix it.[1]

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 99%. That’s in the top 1% of the flaws it scores.[4]

CISA assesses it as not automatable: each attack takes some work.

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]

  1. Check whether you use it.Sophos Firewall 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.
  2. Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 14 Oct 2022 to fix it.
  3. 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

DateEvent
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.[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 99%.[4]

See also

Other Sophos Firewall flaws

Other Sophos flaws

Other code injection flaws

Every Sophos flaw on CISA’s list · Everything added in September 2022

References

  1. ^ Cybersecurity and Infrastructure Security Agency. “Sophos Firewall Code Injection Vulnerability”. Known Exploited Vulnerabilities Catalog, added 23 Sep 2022.
  2. ^ National Institute of Standards and Technology. “CVE-2022-3236 Detail”. National Vulnerability Database, published 23 Sep 2022.
  3. ^ Sophos. Advisories and fixes: sophos.com.
  4. ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.989, percentile 99.9, 31 Oct 2026.
  5. CVE Program. “CVE-2022-3236”. 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.