Wikimedia GrowthExperiments Extension 1.43.7/1.44.4/1.45.2 on Mediawiki infinite loop

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Wikimedia GrowthExperiments Extension 1.43.7/1.44.4/1.45.2 on Mediawiki. This impacts an unknown function. Executing a manipulation can lead to infinite loop. This vulnerability is tracked as CVE-2026-39934. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Wikimedia GrowthExperiments Extension 1.43.7/1.44.4/1.45.2 on Mediawiki. It has been declared as critical. This vulnerability affects an unknown part. The manipulation with an unknown input leads to a infinite loop vulnerability. The CWE definition for the vulnerability is CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Loop with unreachable exit condition ('infinite loop') vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions.This issue affects Mediawiki - GrowthExperiments Extension: 1.45.2, 1.44.4, 1.43.7.

The weakness was disclosed by Urbanecm_WMF and Michael. The advisory is available at phabricator.wikimedia.org. This vulnerability was named CVE-2026-39934 since 04/07/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

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: 7.3
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/07/2026 CVE reserved
04/08/2026 +1 days Advisory disclosed
04/08/2026 +0 days VulDB entry created
04/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: phabricator.wikimedia.org
Researcher: Urbanecm_WMF, Michael
Status: Not defined

CVE: CVE-2026-39934 (🔒)
GCVE (CVE): GCVE-0-2026-39934
GCVE (VulDB): GCVE-100-356002

Entryinfo

Created: 04/08/2026 08:00
Changes: 04/08/2026 08:00 (67)
Complete: 🔍
Cache ID: 216::103

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