CVE-2021-20112
CWE-79Published: July 30, 2021· Updated: Jun 17, 2026
Official Description
A stored cross-site scripting vulnerability exists in TCExam <= 14.8.1. Valid files uploaded via tce_select_mediafile.php with a filename beggining with a period will be rendered as text/html. An attacker with access to tce_select_mediafile.php could upload a malicious javascript payload which would be triggered when another user views the file.
Technical Analysis
CVE-2021-20112 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (2)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-20112 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts