CVE-2026-23873

hustoj is an open source online judge based on PHP/C++/MySQL/Linux for ACM/ICPC and NOIP training. All versions are vulnerable to CSV Injection (Formula Injection) through the contest rank export functionality (contestrank.xls.php and admin/ranklist_export.php). The application fails to sanitize user-supplied input (specifically the "Nickname" field) before exporting it to an .xls file (which renders as an HTML table but is opened by Excel). If a malicious user sets their nickname to an Excel formula when an administrator exports and opens the rank list in Microsoft Excel, the formula will be executed. This can lead to arbitrary command execution (RCE) on the administrator's machine or data exfiltration. A fix was not available at the time of publication.

CVSS

No CVSS.

References

Link	Resource
https://github.com/zhblue/hustoj/security/advisories/GHSA-gqwv-v7vx-2qjw

Configurations

No configuration.

History

22 Jan 2026, 00:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-22 00:15

Updated : 2026-01-26 15:04

NVD link : CVE-2026-23873

Mitre link : CVE-2026-23873

CVE.ORG link : CVE-2026-23873

JSON object : View

Products Affected

No product.

CWE

CWE-1236

Improper Neutralization of Formula Elements in a CSV File

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