CVE-2026-103389
MEDIUM 6.2MISP 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
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 22nd percentile
Impact if exploited
6.2CVSS 4.0 · MEDIUM
- ConfidentialityNone
- IntegrityNone
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ⚠User interaction: Requires active user interaction
- ✓Complexity: No special conditions — reliably repeatable
- ✓Requirements: No special attack requirements
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-103389/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-103389/poc.json
Weakness (CWE)
- CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CWE-20: Improper Input Validation
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
All CVSS metrics
- MEDIUM 6.2 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N - MEDIUM 6.2 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/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