Jmol Plugin - Path Traversal (CVE-2025-34031)

CVE-2025-34031 is a high-severity path traversal vulnerability in the Moodle LMS Jmol plugin (version 6.1 and earlier), where improper input validation in jsmol.php allows unauthenticated attackers to read arbitrary files from the server. By exploiting this flaw, threat actors can access sensitive configuration data, such as database credentials, potentially leading to further compromise of the system. Evidence of active exploitation has already been observed, highlighting the urgency of addressing this issue.

CrowdSec has been tracking this vulnerability and its exploits since 8th of April 2026.

Insights from the CrowdSec network reveal that the attackers trying to exploit CVE-2025-34031 are composed of a fairly even mix of opportunistic and targeted actors. Some attackers employ preliminary reconnaissance, while others use indiscriminate scanning. CrowdSec data also reveals a clear uptick in attacks involving CVE-2025-34031 over the past week. Activity is above the usual baseline, suggesting growing attention from attackers. This may reflect rising awareness, recent exploit releases, or expanded targeting efforts.

Attackers exploit the /filter/jmol/js/jsmol/php/jsmol.php endpoint by supplying a query parameter with a file:// URI, enabling local file inclusion and unauthorized reading of sensitive files from the server.