CVE-2026-54395
MISP contains a reflected cross-site scripting vulnerability in the UiBeta event index view. The urlparams value is inserted into an inline JavaScript handler using HTML escaping inside a single-quoted JavaScript string. Because browsers HTML-decode attribute values before JavaScript parsing, a crafted searcheventinfo value can restore encoded quote characters and break out of the JavaScript string.
An attacker could craft a malicious URL that, when opened by a victim using the UiBeta event index, executes arbitrary JavaScript in the victim’s browser in the context of the MISP instance. The issue is fixed by encoding the value as a JavaScript string literal with json_encode() before applying HTML escaping at the attribute layer.
- ⚠ NVD has not scored this CVE yet - manual triage required (common for recent CVEs)
ATT&CK techniques
1Techniques this CVE enables - linked via CWECAPECATT&CK. High◆ = named directly in ATT&CK or Nuclei templates.
▤ Build a SIEM detection for these techniquesCAPEC attack patterns
6Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.