Sophos Firewall: Improper Control of Generation of Code
CVE-2022-3713 is a high-severity improper control of generation of code vulnerability in Sophos Firewall from Sophos, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions 19.5 GA, 19.0 MR2, 18.5 MR5 as the first without the flaw, so updating Sophos Firewall to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.75% chance of exploitation within 30 days, higher than 55% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Sophos Firewall to 19.5 GA or 19.0 MR2 or 18.5 MR5, whichever matches your release line, or a later version.
- Read the advisory on sophos.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Sophos | Sophos Firewall | before 19.5 GA; before 19.0 MR2; before 18.5 MR5 | 19.5 GA, 19.0 MR2, 18.5 MR5 |
| Sophos | Xg Firewall Firmware | 19.0 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | CNA (sophos.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
A code injection vulnerability allows adjacent attackers to execute code in the Wifi controller of Sophos Firewall releases older than version 19.5 GA.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Control of Generation of Code
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
How developers prevent this class of flaw
- Refactor your program so that you do not have to dynamically generate code.
- Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
- Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.
More Improper Control of Generation of Code vulnerabilities (CWE-94)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Sophos Firewall
- 9.8 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 8.1 High severity
- 7.2 High severity
- 8.8 High severity
Recent Improper Control of Generation of Code vulnerabilities
- 9.8 Critical severity
- 7.2 High severity
- 7.2 High severity
- 9.8 Critical severity
- 7.2 High severity
- 6.8 Medium severity
Mitel MiVoice Connect Code Injection Exploited
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