Vulnerability · Published Oct 20, 2026 · Assigned by VulnCheck

CVE-2026-113683VPL for Moodle before 5.0.0 Reflected XSS via similarity/diff.php filename

Medium 6.1

In plain English

A medium-severity cross-site scripting in moodle-mod_vpl from jcrodriguez-dis. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS 3.1)6.1Medium

Exploit odds (30 days)0.4%top 70.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

VPL (Virtual Programming Lab) for Moodle before 5.0.0 contains a reflected cross-site scripting vulnerability that allows remote attackers to inject script via unencoded filename1/filename2 parameters in similarity/diff.php. Attackers can craft a diff.php link with a JavaScript payload that runs when a user holding mod/vpl:similarity opens it, performing actions or disclosing data under their session.

Affected products (as reported)

Vendor	Product	Versions
jcrodriguez-dis	moodle-mod_vpl	0 – before 5.0.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/jcrodriguez-dis/moodle-mod_vpl/commit/5dd7fe00df2816b692f8ea262c6fa8cdee0b26b7 patch
VPL V5.0.0 Release Notes release-notes
https://github.com/jcrodriguez-dis/moodle-mod_vpl/blob/V4.5.0/similarity/diff.class.php#L412-L419 technical-description
VulnCheck Advisory: VPL for Moodle before 5.0.0 Reflected XSS via similarity/diff.php filename third-party-advisory