CVE-2026-28405
MarkUs: Stored XSS in Submission HTML Preview Enables Instructor-Context Actions
- State
- Published
- Severity
- 8.0 High
- Published
- Mar 5, 2026
- Updated
- Mar 6, 2026
- Reserved
- Feb 27, 2026
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 | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 8.0 High | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H | GitHub_M |
Weaknesses
- CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Products
| Product | Versions |
|---|---|
MarkusMarkUsProject |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.