Arbitrary File Write leading up to remote code execution (instructor accounts)
Published Nov 18, 2024 · Updated Nov 3, 2026
Original summary
Normalized public record · Updated Nov 3, 2026
Arbitrary File Write leading up to remote code execution (instructor accounts)
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
MarkUs is a web application for the submission and grading of student assignments. In versions prior to 2.4.8, an arbitrary file write vulnerability in the update/upload/create file methods in Controllers allows authenticated instructors to write arbitrary files to any location on the web server MarkUs is running on (depending on the permissions of the underlying filesystem). e.g. This can lead to a delayed remote code execution in case an attacker is able to write a Ruby file into the config/initializers/ subfolder of the Ruby on Rails application. MarkUs v2.4.8 has addressed this issue. No known workarounds are available at the application level aside from upgrading.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- MEDIUM
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Nov 18, 2024 · Last refreshed Nov 3, 2026