Known exploited · Sophos

CVE-2020-15069: Sophos XG Firewall Buffer Overflow Vulnerability

What it is

Sophos XG Firewall contains a buffer overflow vulnerability that allows for remote code execution via the "HTTP/S bookmark" feature.

Added February 6, 2025Due February 27, 2025CISA KEV catalog 2026.10.01

Vendor: Sophos
Product: XG Firewall
Added to KEV: February 6, 2025
CISA due date: February 27, 2025
Ransomware use: Unknown
Weakness: CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

What CISA requires

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Find every instance of XG Firewall you run, including the forgotten ones, and check its version against the vendor advisory.
Apply the vendor's fix or mitigation, before February 27, 2025 if you are bound by CISA's deadline, sooner if it faces the internet.
Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.

H2 Security

We check where you run it, patch or mitigate with your team, and look for signs it was already used against you.

T Academy

Security engineering on real hosts in the browser, every objective checked on the machine. The first two lessons of Linux 1 are free.

Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.