CVE-2026-25962 in Markus
Summary
by MITRE • 03/06/2026
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.
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Analysis
by VulDB Data Team • 03/12/2026
The vulnerability identified as CVE-2026-25962 affects MarkUs, a web-based platform designed for academic assignment submission and grading. This application processes zip file uploads from both instructors and students, creating a potential attack surface that requires careful consideration of file handling security practices. The flaw exists in the extraction mechanism that lacks proper validation controls, making it susceptible to malicious exploitation through carefully crafted archive files.
The technical implementation of this vulnerability stems from the absence of size and entry-count limits during zip file extraction processes. When instructors upload zip files containing assignment configurations or when students submit assignments as compressed archives, the system performs extraction without imposing restrictions on the number of files or total size of the archive contents. This design flaw directly maps to CWE-400, which addresses Uncontrolled Resource Consumption, specifically targeting the lack of proper input validation and resource limits in archive processing. The vulnerability allows an attacker to potentially trigger resource exhaustion through maliciously constructed zip files that contain excessive entries or oversized compressed data.
The operational impact of this vulnerability extends beyond simple resource consumption issues, as it creates opportunities for denial-of-service attacks that can severely disrupt academic operations. When attackers exploit this weakness, they can overwhelm system resources such as memory and storage space, potentially causing the MarkUs application to become unresponsive or crash entirely. This disruption affects not only the availability of the grading system but also impacts the academic workflow for both instructors and students who rely on timely submission and feedback mechanisms. The vulnerability particularly affects the assignment submission and grading processes, which are core functions of the platform, potentially leading to missed deadlines and academic disruptions.
Mitigation strategies for this vulnerability should focus on implementing comprehensive resource limits during archive processing. Organizations should immediately upgrade to MarkUs version 2.9.4 or later, which includes the necessary patches to address this issue. Additionally, system administrators should implement monitoring and alerting mechanisms to detect unusual resource consumption patterns that might indicate exploitation attempts. The remediation approach aligns with ATT&CK technique T1499.004, which covers resource exhaustion via archive manipulation, emphasizing the need for proper input validation and resource management controls. Security measures should include setting maximum file count limits, imposing size restrictions on extracted archives, and implementing proper logging of archive processing activities to enable forensic analysis if exploitation occurs.