CVE-2025-62663: The Wikimedia Foundation Mediawiki – UploadWizard Extension · XSS or 'Cross-site Scripting'
Affects The Wikimedia Foundation Mediawiki – UploadWizard ExtensionSource CVE Database V5
Not known to be exploited · CVSS 6.9 Medium : upgrade to 1.39 when convenient.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.39
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:LExploitation evidence
Disclosed: evidence found.
CVE published 18 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade The Wikimedia Foundation Mediawiki – UploadWizard Extension to 1.39.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The Wikimedia Foundation Mediawiki - UploadWizard Extension | Affected
| Fixed in
|
AI-suggested
To mitigate CVE-2025-62663 effectively, European organizations should: 1) Monitor the Wikimedia Foundation’s official channels for the release of a security patch for the UploadWizard extension and apply updates promptly once available. 2) In the interim, consider disabling the UploadWizard extension if feasible to eliminate the attack surface. 3) Implement strict input validation and output encoding on any user-generated content within Mediawiki to prevent injection of malicious scripts. 4) Deploy Content Security Policies (CSP) to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 5) Conduct regular security audits and penetration testing focused on web application vulnerabilities, including XSS. 6) Educate users and administrators about the risks of XSS and encourage vigilance for suspicious activity or unexpected behavior in Mediawiki instances. 7) Employ web application firewalls (WAFs) with rules designed to detect and block XSS payloads targeting Mediawiki. 8) Review and limit user permissions to reduce the likelihood of malicious content being uploaded or edited by unauthorized users. These measures, combined with timely patching, will significantly reduce the risk posed by this vulnerability.
Description
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in The Wikimedia Foundation Mediawiki - UploadWizard Extension allows Stored XSS.This issue affects Mediawiki - UploadWizard Extension: from master before 1.39.