CVE-2026-123309
MEDIUMCVSS 6.1/10
Last modified
CVE-2026-123309 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. In JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 stored XSS was possible on the built-in web server via Markdown preview.
Description
In JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 stored XSS was possible on the built-in web server via Markdown preview
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| JetBrains | IntelliJ IDEA | < 2026.3, 2026.2.4 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
What is CVE-2026-123309?
In JetBrains IntelliJ IDEA before 2026.3,
2026.2.4 stored XSS was possible on the built-in web server via Markdown preview
How severe is CVE-2026-123309?
CVE-2026-123309 has a CVSS score of 6.1/10 (MEDIUM severity).
How do I fix CVE-2026-123309?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-123309?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST