CVE-2026-81820

Affected versions of Flowintel construct timeline HTML using attacker-controllable MISP object fields such as: * object UUID; * object name; * attribute value; * attribute type; * comment; * first/last seen values; * IDS flag. Those values were concatenated directly into HTML strings before rendering. The upstream commit explicitly states that DOMPurify removed XSS vectors but still allowed other HTML elements, such as forms, through. The fix replaces direct string interpolation with DOM construction via document.createElement() and assigns all attacker-controlled values using textContent. The headline is similarly converted to escaped HTML through a temporary element. Version impacted =>3.3.0

CVSS

No CVSS.

References

Link	Resource
https://github.com/flowintel/flowintel/commit/11f71e747d95ed062667e2df0ce259c5fa64d531.patch

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:21

Updated : 2026-08-28 15:28

NVD link : CVE-2026-81820

Mitre link : CVE-2026-81820

CVE.ORG link : CVE-2026-81820

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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