Quick answers
- Is CVE-2026-123323 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123323 being exploited in the wild.
- How severe is CVE-2026-123323?
- High severity, with a CVSS score of 8.4, published 6 November 2026.
- Which products and versions are affected?
- Jetbrains YouTrack before 2025.3.170763, 2026.1.14150, 2026.2.19656.
- Is there a fix for CVE-2026-123323?
- Yes: fixed in YouTrack 2025.3.170763, 2026.1.14150, 2026.2.19656. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123323 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-123323?
- Check whether you run Jetbrains YouTrack at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: YouTrack 2025.3.170763, 2026.1.14150, 2026.2.19656
Technical details
The vulnerability stems from improper URL validation in the app widget host component of YouTrack, which fails to enforce user confirmation before allowing widgets to send REST requests. An attacker who controls or tricks a user into loading a malicious app widget could execute arbitrary REST API calls within the YouTrack instance with the user's privileges. This is a client-side authorization bypass that requires user interaction to load the widget.
Affected products
- JetBrains YouTrack before 2025.3.170763, 2026.1.14150, 2026.2.19656
Timeline
- 2026-11-06: disclosed