Is CVE-2026-27166 actively exploited?

No active exploitation of CVE-2026-27166 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-27166 be exploited remotely?

Yes. CVE-2026-27166 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-27166?

CVE-2026-27166 has a CVSS score of 5.4 (MEDIUM).

HOME VULNERABILITIESCVE-2026-27166

MEDIUM

CVE-2026-27166

CWE-80Published: March 19, 2026· Updated: Mar 25, 2026

5.4

CVSS v3.1

EPSS:0.03%probability of exploitation in 30 daysPercentile:8.4th

Official Description

Discourse is an open source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1 and 2026.1.2, insufficient cleanup in the default Codepen allowed iframes value allows an attacker to trick a user into changing the URL of the main page. This issue has been fixed in versions 2026.3.0-latest.1, 2026.2.1 and 2026.1.2. To workaround this issue, remove Codepen from the list of allowed iframes.

NVD Source

Technical Analysis

CVE-2026-27166 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.