CVE-2026-103388
Deferred
Deferred - Pending Action
Stored XSS in MISP Galaxy Cluster Source Field
Vulnerability report for CVE-2026-103388, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-30
Last updated on: 2026-09-30
Assigner: CIRCL
Description
Description
MISP renders the source field of a Galaxy Cluster as a clickable hyperlink whenever the stored value passes PHP's FILTER_VALIDATE_URL validation. Because FILTER_VALIDATE_URL accepts the javascript: URI scheme, a user with galaxy editor privileges on the local instance or on a synced instance could store a javascript: URL as the cluster source.
When another user views the affected Galaxy Cluster and clicks the rendered link, the embedded script executes in the victim's browser context, enabling session hijacking, data exfiltration, or actions performed on behalf of the victim.
Preconditions:
- Attacker must hold galaxy editor privileges (local or via sync).
- Victim must view the affected cluster and click the malicious link.
Impact:
- Stored cross-site scripting (XSS) in the victim's browser.
- Potential session theft, credential harvesting, or unauthorized actions within the MISP application.
Affected: <2.5.48.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| misp | misp | to 2.5.48 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| 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. |
