MISP Stored Cross-Site Scripting via Unvalidated Galaxy Icon Field in Correlation Graph (CVE-2026-103389) | HOL Guard CVE

Medium · CVSS 6.2CVE-2026-103389

MISP Stored Cross-Site Scripting via Unvalidated Galaxy Icon Field in Correlation Graph

Answer in brief

CVE-2026-103389 records a Medium severity (CVSS 6.2) vulnerability in MISP Stored Cross-Site Scripting via Unvalidated Galaxy Icon Field in Correlation Graph. The current sources do not mark it as known exploited. The current feed maps MISP/MISP (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 30, 2026Updated Sep 30, 2026Source checked Sep 30, 2026First seen by HOL Sep 30, 2026Material review Sep 30, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.2
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps MISP/MISP (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
MISP/MISPgeneric	>=0 <2.5.48	2.5.48

Recommended response

Check inventory. Check lockfiles and deployed manifests for MISP/MISP.
Review the reported fix. Source-reported solution: The vulnerability is remediated by enforcing strict input validation on the galaxy icon field so that only valid Font Awesome icon names (lowercase alphanumeric characters and dashes) are accepted at write time. The sync/import capture path discards any icon value that does not conform. The correlation graph JSON generation falls back to a safe default icon for any previously stored invalid value. On the client side, both correlation graph scripts now set the icon as a CSS class attribute rather than injecting it as raw HTML, and apply an additional regex sanitization pass. The asset cache-busting version is incremented to ensure browsers load the corrected scripts.

Evidence timeline and material changes

Published upstream
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 30, 2026

Sources and claim methodology

GitHub security advisorygithub.com

Upstream source description

MISP contains a stored cross-site scripting (XSS) vulnerability in the galaxy icon handling path. The icon field of a galaxy object was persisted without any server-side validation through the galaxy add, edit, and sync/import capture endpoints. The stored value was subsequently concatenated directly into HTML markup by the D3-based correlation graph rendering scripts (both the default and Overmind themes) using the .html() method. A user holding the perm_galaxy_editor permission, which is granted to the stock User role, could store arbitrary HTML or JavaScript in the icon field. Any other user who opened the correlation graph of an event containing a cluster belonging to that galaxy would have the injected script executed in their browser session. Impact: - Arbitrary script execution in the context of the victim's MISP session - Potential theft of session credentials, manipulation of displayed data, or initiation of actions on behalf of the victim - Affects both the default and Overmind UI themes Affected versions: <2.5.48

Quoted source text, attributed separately from HOL analysis.