Stored Cross-Site Scripting in Altium Live Support Center Comment Endpoint
Published Jan 15, 2026
6.1
MEDIUMCVSS 3.1
EPSS 0.29%
Description
A stored cross-site scripting (XSS) vulnerability exists in the Altium Support Center AddComment endpoint due to missing server-side input sanitization. Although the client interface applies HTML escaping, the backend accepts and stores arbitrary HTML and JavaScript supplied via modified POST requests.
The injected content is rendered verbatim when support cases are viewed by other users, including support staff with elevated privileges, allowing execution of arbitrary JavaScript in the victim’s browser context.
Affected products
-
- Version 0StatusaffectedConstraints<=1.1.1.39
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Altium | Altium Live | unaffected |
|
- ≤ 1.1.1.39
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Jan 16, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
Jan–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.29% (0.00289) | 19.54th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.26% (0.00256) | 16.68th | v5 (v2026.06.15) |
| Jan 16, 2026 | 0.04% (0.00036) | 10.53th | v4 (v2025.03.14) |
References (1)
| Link | Providers | Tags |
|---|---|---|
| https://www.altium.com/platform/security-compliance/security-advisories | Vendor Advisory |
Change history (0)
No recorded changes yet.