CVE-2026-73373: CWE-434 Unrestricted Upload of File with Dangerous Type in Joomla! Project Joomla! CMS
Joomla! Core - [20260810] - Unrestricted uploads of SHTML files in Joomla 1.0.0-5.4.7, 6.0.0-6.1.2 - The default list of dangerous files did not include SHTML files. On servers that executed these files, that could lead to code execution.
AI Analysis
Technical Summary
CVE-2026-73373 is a vulnerability in Joomla! CMS where the default list of dangerous files does not include SHTML files, allowing unrestricted upload of these files. This affects Joomla versions 1.0.0 to 5.4.6 and 6.0.0 to 6.1.2. If the server executes SHTML files, an attacker could upload malicious SHTML files leading to code execution. The vulnerability is identified as CWE-434 (Unrestricted Upload of File with Dangerous Type). The CVSS 4.0 base score is 8.9, indicating high severity. There is no vendor advisory or patch information available at this time.
Potential Impact
Successful exploitation can lead to remote code execution on affected Joomla! CMS installations if the server executes uploaded SHTML files. This could allow attackers to run arbitrary code with the privileges of the web server, potentially leading to full system compromise depending on server configuration.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, administrators should consider restricting file uploads to exclude SHTML files manually or configure the server to not execute SHTML files. Monitoring and additional access controls may help mitigate risk but are not a substitute for an official patch.
CVE-2026-73373: CWE-434 Unrestricted Upload of File with Dangerous Type in Joomla! Project Joomla! CMS
Description
Joomla! Core - [20260810] - Unrestricted uploads of SHTML files in Joomla 1.0.0-5.4.7, 6.0.0-6.1.2 - The default list of dangerous files did not include SHTML files. On servers that executed these files, that could lead to code execution.
CVSS v4.0
Score 8.9high
Affected software
pkg:github/joomla/joomla-cmsRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-73373 is a vulnerability in Joomla! CMS where the default list of dangerous files does not include SHTML files, allowing unrestricted upload of these files. This affects Joomla versions 1.0.0 to 5.4.6 and 6.0.0 to 6.1.2. If the server executes SHTML files, an attacker could upload malicious SHTML files leading to code execution. The vulnerability is identified as CWE-434 (Unrestricted Upload of File with Dangerous Type). The CVSS 4.0 base score is 8.9, indicating high severity. There is no vendor advisory or patch information available at this time.
Potential Impact
Successful exploitation can lead to remote code execution on affected Joomla! CMS installations if the server executes uploaded SHTML files. This could allow attackers to run arbitrary code with the privileges of the web server, potentially leading to full system compromise depending on server configuration.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, administrators should consider restricting file uploads to exclude SHTML files manually or configure the server to not execute SHTML files. Monitoring and additional access controls may help mitigate risk but are not a substitute for an official patch.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Joomla
- Date Reserved
- 2026-08-12T14:00:09.041Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8482f1c6e8be03326f9ab1
Added to database: 08/18/2026, 16:06:09 UTC
Last enriched: 08/18/2026, 16:20:14 UTC
Last updated: 08/18/2026, 16:35:06 UTC
Views: 4
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