CVE-2026-103664: MISP Reflected Cross-Site Scripting via Unsanitized Analyst Data Seed Parameter
MISP contains a reflected cross-site scripting (XSS) vulnerability in the analyst data notes panel. The seed path parameter, supplied by the user via the URL, was passed directly into inline JavaScript within the rendered HTML response without any sanitization or type enforcement.
An attacker who can convince an authenticated MISP user to navigate to a crafted URL (for example, via a phishing link) can inject arbitrary JavaScript that executes in the victim's browser context. This may allow the attacker to read session tokens, manipulate the page, or perform actions on behalf of the victim.
Preconditions:
- The victim must be authenticated to MISP and access the analyst data view for an attribute or object.
- The attacker must supply a malicious seed value in the URL path.
Impact:
- Execution of arbitrary JavaScript in the victim's browser session.
- Potential theft of session credentials or sensitive data visible in the page.
- Manipulation of the analyst data interface.
Affected: MISP versions prior to the fix (commit 58925dbf0, post v2.5.48).
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
MISPto a version that resolves this vulnerability.Patch 58925dbf0
Event History
Frequently Asked Questions
Which users are exposed to this issue?
Authenticated MISP users who access the analyst data view for an attribute or object are exposed if they follow a crafted URL containing a malicious seed path value.
What does an attacker need to exploit it?
The attacker needs to supply a malicious seed value in a URL path and convince an authenticated user to open that URL, such as through a phishing link. No direct access to the victim's MISP session is stated as necessary.
What can the injected script do in an affected user's session?
It can execute arbitrary JavaScript in the victim's browser context. This may allow session-token theft, access to sensitive data visible on the page, or actions and interface manipulation performed as the victim.
Which versions should be remediated?
MISP versions before the fix identified by commit 58925dbf0 are affected. The fix is described as post-v2.5.48.