CVE-2026-10856
MediumCVSS 6.1Exploitation Probability (EPSS)
Low risk4th percentile - higher than 4% of all known CVEs
Summary
A URL validation flaw in the MISP dashboard allowed a crafted URL to be accepted as a local path while being interpreted by browsers as an external URL. This flaw enabled attackers to create buttons that appeared to lead inside the application but redirected users to attacker-controlled sites.
Risk Assessment
The organization may be exposed to phishing attacks, credential theft, and user manipulation, potentially leading to serious security breaches.
Recommendation
It is recommended to update to the latest version of MISP, which fixes this issue by rejecting empty paths and paths starting with /\, and by emitting only the validated URL in the href attribute.
Original NVD description (English source)
A URL validation flaw in the MISP dashboard button widget allowed a crafted relative-looking URL to be accepted as a local path while being interpreted by browsers as an external URL. The validation rejected URLs containing an explicit scheme, host, or user component, but did not reject paths beginning with a slash followed by a backslash, such as /\example.com. Some browsers normalize backslashes in URLs as forward slashes, which can turn this into a scheme-relative external navigation target. In addition, the generated href concatenated the reconstructed URL with the original URL, increasing the possibility of unsafe or malformed link generation. An attacker able to configure or influence a dashboard button URL could craft a button that appears to point inside the application but redirects users to an attacker-controlled site when clicked. This could be used for phishing, credential theft, or social engineering. The patch fixes the issue by rejecting empty paths and paths starting with /\, and by emitting only the reconstructed validated URL in the anchor href.