CVE-2025-54476: Joomla! CMS · Cross-site Scripting
Affects Joomla! CMSSource CVE Database V5
Not known to be exploited · CVSS 4.8 Medium.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Sep 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Joomla! Project Joomla! CMS | Affected
| Fixed in– |
AI-suggested
European organizations should implement the following specific mitigations: 1) Immediately audit Joomla! CMS installations to identify affected versions and plan for upgrades to patched versions once available. 2) Employ web application firewalls (WAFs) with custom rules to detect and block suspicious input patterns targeting the checkAttribute method or typical XSS payloads. 3) Enforce strict Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 4) Conduct thorough input validation and output encoding on all user-supplied data at the application level, supplementing Joomla!'s native filtering. 5) Limit user privileges to the minimum necessary to reduce the risk posed by the PR:H requirement. 6) Educate users about phishing and social engineering risks to mitigate the UI:P factor. 7) Monitor logs for unusual activity indicative of attempted exploitation. 8) Stay informed on Joomla! security advisories for official patches and apply them promptly. These measures collectively reduce the likelihood and impact of exploitation beyond generic advice.
Description
Improper handling of input could lead to an XSS vector in the checkAttribute method of the input filter framework class.