CVE-2026-29052 HumHub Calendar Module: Stored XSS in Event Types
Stored XSS in HumHub Calendar module allows attackers to execute scripts in users' browsers via malicious event types.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-29052?
CVE-2026-29052 is a medium-severity cross-site scripting vulnerability in humhub calendar, published on 5 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Calendar module for HumHub enables users to create one-time or recurring events, manage attendee invitations, and efficiently track all scheduled activities. Prior to version 1.8.11, a Stored Cross-Site Scripting (XSS) vulnerability in the Event Types of the HumHub Calendar module impacts users viewing events created by an administrative account. This issue has been patched in version 1.8.11.
Weakness: CWE-79
Which versions are affected by CVE-2026-29052?
It affects 1 product.
Products include Humhub Calendar.
How do I fix CVE-2026-29052?
No fix has been published for CVE-2026-29052 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-29052 being exploited?
There is no known exploitation of CVE-2026-29052 in the wild and no public exploit code.
Sources
Also known as GHSA-gqj3-pmp2-mrx8.