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CVE-2022-3236Sophos Firewall Code Injection Vulnerability

Patch nowCritical9.8Exploited, CISA due date 2022-10-14EPSS 99%, higher than 100% of scored CVEs

CVE-2022-3236 is a code injection in Sophos Firewall, rated critical (9.8 on CVSS 3.1).

Why this priority: Exploited in the wild: listed in CISA's KEV catalog.

Published · Updated · NVD status: Analyzed

What it is

Input is evaluated as code by the application, so an attacker's code runs inside it.

How it is reached

An attacker can exploit it over the network, without an account, and nobody has to click anything.

What an attacker gains

A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker run commands or code with the privileges of the affected service.

Is it being exploited?

CISA added it to the Known Exploited Vulnerabilities catalog on 2022-09-23: it is being exploited in the wild. EPSS estimates a 99% chance of exploitation activity in the next 30 days, higher than 100% of scored CVEs.

What to do

  1. Treat it as urgent: it is on CISA's KEV list. CISA's deadline for US federal agencies: 2022-10-14.
  2. No fixed version is listed yet. Find every place Sophos Firewall runs, watch the references for a fix, and plan a replacement if it is no longer supported.
  3. While there is no fix, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
  4. Check exposed instances for signs of compromise, not only for the version.

Description from NVD

A code injection vulnerability in the User Portal and Webadmin allows a remote attacker to execute code in Sophos Firewall version v19.0 MR1 and older.

What this means for your architecture.

A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.

Components it touches

  • Network edge devices: VPNs, firewalls, routers and gateways. They sit between the internet and internal networks, so a flaw in one is often the first step into everything behind it.
  • Application servers and the hosts they run on. The flaw sits between untrusted input and code or command execution.
  • Template engines. The flaw sits between untrusted input and code or command execution.

Trust boundaries in play

  • Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
  • Between untrusted input and code or command execution. An attacker who crosses it can run commands or code with the privileges of the affected service.

Questions to answer about your own systems

  • Where does Sophos Firewall run in your systems, and at which version?
  • Which of those instances can be reached from the internet or partner networks?
  • What can it reach once compromised: which data stores, secrets and services?

Sources

  • CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
  • Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
  • Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
  • Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.