CVE-2026-73373: Joomla! Core - [20260810] - Unrestricted uploads of SHTML files in Joomla 1.0.0-5.4.7, 6.0.0-6.1.2

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-18 · updated 2026-10-22
Weakness: CWE-434

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.

Affected products

Joomla!: from 1.0.0 before 5.4.8; from 6.0.0 before 6.1.3 — fixed in 5.4.8, 6.1.3

How to fix

Upgrade to a fixed version: Joomla! 5.4.8, 6.1.3. Check the vendor advisory for mitigations.

References

https://developer.joomla.org/security-centre/1077-20260810-core-unrestricted-uploads-of-shtml-files.html
https://www.joomla.org/

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