SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2025-6704

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…

CRITICAL 9.8EPSS 9.33%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (9.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
9.33% probability · 95th percentile
CISA KEV
Not listed
Weakness
CWE-78
Affected
sophos/firewall firmware
Source
security-alert@sophos.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.