CVE-2025-6704: Sophos Firewall · OS Command Injection
Affects Sophos FirewallSource CVE Database V5
Not known to be exploited · 11% EPSS · CVSS 9.8 Critical.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 11.7% chance of exploitation in 30 days – higher than 96% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 21 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Sophos Sophos Firewall | Affected
| Fixed in– |
AI-suggested
Immediate mitigation steps include disabling the Secure PDF eXchange (SPX) feature if it is not essential, especially in environments where High Availability mode is enabled. Organizations should review their firewall configurations to identify if the vulnerable SPX configuration is active and consider temporarily disabling HA mode if feasible until a patch is available. Network segmentation and strict access controls should be enforced to limit exposure of management interfaces to untrusted networks. Monitoring firewall logs for unusual activity related to SPX or HA operations can help detect attempted exploitation. Additionally, organizations should subscribe to Sophos security advisories to promptly apply patches once released. Employing intrusion detection/prevention systems (IDS/IPS) to detect anomalous command injection patterns targeting the firewall can provide an additional layer of defense. Finally, conducting internal audits and penetration tests focusing on firewall configurations can help identify and remediate potential weaknesses proactively.
Description
An arbitrary file writing vulnerability in the Secure PDF eXchange (SPX) feature of Sophos Firewall versions older than 21.0 MR2 (21.0.2) can lead to pre-auth remote code execution, if a specific configuration of SPX is enabled in combination with the firewall running in High Availability (HA) mode.