CVE-2026-93296: MISP Overmind: Stored Cross-Site Scripting via Unescaped Object Names in Statistics Legends

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of 29 Oct 2026. If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?

0.4%

EPSS score, percentile 33 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

8.5 High

CVSS v4.0 base score, given by the CNA

What should I do?

The fix applies HTML output encoding to the user-controlled label variable (lbl) before it is interpolated into the innerHTML string in both affected view templates. Full textSolution from the CVE record.

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (1)

Which versions are affected?

Affected

• before 2.5.47

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 29 Oct 2026. About the data.

What to do

Solution (from the CVE record)

The fix applies HTML output encoding to the user-controlled label variable (lbl) before it is interpolated into the innerHTML string in both affected view templates. By wrapping the label with escapeHtml(), any HTML metacharacters in object names are neutralized, preventing injected markup from being interpreted as executable HTML or JavaScript in the viewer's browser.

Advisories and patches

• Security patch (Patch)

This summary is based on the CVE record as of 29 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

As listed in the CVE record.

Versions not listed are: unaffected.

Source: CVE List, as of 29 Oct 2026. About the data.

About this vulnerability

MISP contains a stored cross-site scripting (XSS) vulnerability in the Overmind theme's statistics views. The event General card and the server/feed preview card constructed donut chart legend labels by directly concatenating object name or category keys into an innerHTML string without HTML-encoding. Because MISP object names are user-controllable by any authenticated user with sufficient permis…

Summary: CVE record, as of 29 Oct 2026.

• CISA has not added CVE-2026-93296 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
• The CVE record was published on 17 Sep 2026.
• The CVE record carries a CVSS v4.0 base score of 8.5 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.4% (percentile 33), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
• CISA's SSVC assessment in the CVE record: exploitation none, automatable no, technical impact partial.
• The credits in the CVE record name Anthropic (Claude) as finder.

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; CVE List, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026. About the data.

Description

MISP Overmind: Stored Cross-Site Scripting via Unescaped Object Names in Statistics Legends

MISP contains a stored cross-site scripting (XSS) vulnerability in the Overmind theme's statistics views. The event General card and the server/feed preview card constructed donut chart legend labels by directly concatenating object name or category keys into an innerHTML string without HTML-encoding. Because MISP object names are user-controllable by any authenticated user with sufficient permissions to create or modify such objects, an attacker could craft a name containing malicious markup. When any other user viewed the affected Overmind dashboard, the injected markup would be interpreted as live HTML/JavaScript in the victim's browser, executing in the context of the MISP application origin. This could allow session hijacking, data exfiltration, or arbitrary actions performed on behalf of the victim.  The vulnerability requires the attacker to have low-level authenticated access to create or rename an object whose name is rendered in the legend, and the victim to view the Overmind event or server preview page. No special browser conditions or race conditions are required.

Source: CVE List, as of 29 Oct 2026. About the data.

Timeline