CVE-2026-86440
Received
Received - Intake
Open Redirect and XSS in MISP Dashboard Widgets
Vulnerability report for CVE-2026-86440, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-07
Last updated on: 2026-09-07
Assigner: CIRCL
Description
Description
Affected versions of MISP insufficiently validate URLs used by dashboard widgets, particularly the Button widget.
The widget's URL is stored configuration controlled by a user. The previous renderer considered a URL safe if it appeared relative or if its parsed hostname matched the configured MISP hostname. That logic failed to reject dangerous schemes and URL forms that browsers normalize differently from PHP's URL parsing.
As a result, values such as javascript: URLs or backslash-based authority forms could reach the generated anchor's href and execute script or navigate to an attacker-controlled origin when another user interacted with the widget. The upstream commit describes the issue as:
“javascript: and backslash URLs reached the href (stored XSS)”.
The fix routes widget URLs through a shared DashboardURLValidator, rejects dangerous schemes, raw backslashes, control characters, and unauthorized absolute origins, and validates the URL both in the widget handler and renderer.
Version affected: ≤2.5.45
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| misp | misp | to 2.5.45 (inc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-20 | The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. |
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
