Moodle Virtual Programming Lab up to 4.x Similarity Diff similarity/diff.php filename1/filename2 cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k2.30

Summaryinfo

A vulnerability labeled as problematic has been found in Moodle Virtual Programming Lab up to 4.x. The impacted element is an unknown function of the file similarity/diff.php of the component Similarity Diff. The manipulation of the argument filename1/filename2 results in cross site scripting. This vulnerability is known as CVE-2026-113683. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Moodle Virtual Programming Lab up to 4.x. It has been classified as problematic. Affected is an unknown part of the file similarity/diff.php of the component Similarity Diff. The manipulation of the argument filename1/filename2 with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-113683 since 10/20/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

By approaching the search of inurl:similarity/diff.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 5.0.0 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.1
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Google Hack: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Virtual Programming Lab 5.0.0

Timelineinfo

10/20/2026 Advisory disclosed
10/20/2026 +0 days CVE reserved
10/20/2026 +0 days VulDB entry created
10/20/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-113683 (🔒)
GCVE (CVE): GCVE-0-2026-113683
GCVE (VulDB): GCVE-100-422880

Entryinfo

Created: 10/20/2026 18:14
Changes: 10/20/2026 18:14 (79)
Complete: 🔍
Cache ID: 216::103

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