CVE-2026-103321

MISP contains a stored cross-site script (XSS) vulnerability in the event graph preview feature. The event graph preview image field was accepted and stored without server-side validation. On the client side, the stored value was rendered into an HTML img element's src attribute via string concatenation, allowing a crafted value to break out of the attribute context and inject arbitrary script. Preconditions: - An authenticated MISP user with the ability to create or modify an event graph entry. - A second user (the victim) who views the event graph and triggers the preview popover. Impact: - Execution of arbitrary JavaScript in the victim's browser within the MISP application context. - Potential theft of session tokens, cookies, or sensitive data accessible to the victim's browser. - Potential for performing actions on behalf of the victim within the MISP application. Affected: MISP versions prior to the fix (commit applied after v2.5.48).

CVSS

No CVSS.

References

Link	Resource
https://github.com/MISP/MISP/commit/92c7ccc43

Configurations

No configuration.

History

30 Sep 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 13:17

Updated : 2026-09-30 13:17

NVD link : CVE-2026-103321

Mitre link : CVE-2026-103321

CVE.ORG link : CVE-2026-103321

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-79

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

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