CVE-2026-28405

HIGH

MarkUs <2.9.1 - XSS

Title source: llm
STIX 2.1

Description

MarkUs is a web application for the submission and grading of student assignments. Prior to version 2.9.1, the courses/<:course_id>/assignments/<:assignment_id>/submissions/html_content route reads the contents of a student-submitted file and renders them without sanitization. This issue has been patched in version 2.9.1.

Scores

CVSS v3 8.0
EPSS 0.0004
EPSS Percentile 11.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-79
Status published
Products (1)
markusproject/markus < 2.9.1
Published Mar 05, 2026
Tracked Since Mar 06, 2026