MISP DOM-based Cross-Site Scripting via innerHTML in Contextual Menu

published 2026-09-21 49 d ago modified 2026-09-21 49 d ago also EUVD-2026-83903

cvss: 6.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits: 0; none known

MISP contains a DOM-based cross-site scripting (XSS) vulnerability in the contextual menu JavaScript component. The ContextualMenu class populates HTML <option> elements by assigning user-controllable values to the innerHTML property. Because innerHTML parses and renders HTML markup, any untrusted string supplied as the option text (value.text or value) is interpreted as live DOM content rather than plain text. An attacker who can influence the data rendered in the contextual menu can inject arbitrary HTML or JavaScript that executes in the victim's browser within the MISP application origin. This may allow session hijacking, data exfiltration, or unauthorized actions performed on behalf of the authenticated user.

Version affected: <2.5.47

Patch / fix

fixed in 1 links 1

MISP MISP 2.5.47

github.com/MISP/MISP@b062698 commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 49 d ago (2026-09-21)

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
CNA	4.0	6.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

MISP MISP

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

github.com /MISP/MISP/commit/b062698f2
patch

Sources

CVE List CVE-2026-94373
NVD CVE-2026-94373

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary