CVE-2026-73679

ImpressCMS contains an authenticated remote code execution vulnerability in the custom tag module that allows authenticated administrators to execute arbitrary PHP code by storing a malicious payload in a custom tag with PHP type enabled. The application decodes HTML-encoded content via undoHtmlSpecialChars() before passing it to eval() in the renderWithPhp() method, bypassing HTML Purifier sanitization, and the payload is triggered on every frontend page load through the preload event system.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/DevVaibhav07/VULN-POC/blob/main/ImpressCMSRCCE.md
https://github.com/ImpressCMS/impresscms
https://www.vulncheck.com/advisories/impresscms-authenticated-rce-via-php-custom-tag-eval

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-14 19:18

Updated : 2026-08-26 16:57

NVD link : CVE-2026-73679

Mitre link : CVE-2026-73679

CVE.ORG link : CVE-2026-73679

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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