CVE-2026-25962 MarkUs: Zip bomb in config upload enables DoS

Medium 6.5 Published 6 Mar 2026 Updated 6 Mar 2026

Attackers can cause denial of service by uploading malicious zip bombs to the MarkUs web application due to missing extraction limits.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-25962?

CVE-2026-25962 is a medium-severity denial of service vulnerability in MarkUsProject Markus, published on 6 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

MarkUs is a web application for the submission and grading of student assignments. Prior to version 2.9.4, MarkUs currently extracts zip files without any size or entry-count limits. For example, instructors can upload a zip file to provide an assignment configuration; students can upload a zip file for an assignment submission and indicate its contents should be extracted. This issue has been patched in version 2.9.4.

Weakness: CWE-409

Which versions are affected by CVE-2026-25962?

It affects 1 product.

Products include Markusproject Markus.

How do I fix CVE-2026-25962?

No fix has been published for CVE-2026-25962 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-25962 being exploited?

There is no known exploitation of CVE-2026-25962 in the wild and no public exploit code.

Sources

Also known as GHSA-x8xv-j7fc-65x5.