CVE-2026-100263
Medium
Description
In JetBrains YouTrack before 2026.2.18991 stored HTML injection via the User-Agent header was possible
SeverityMedium
CVSS4.7
Exploit probability—
Product
Jetbrains Youtrack
PublishedSep 30, 2026
First seenSep 30, 2026
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- jetbrains youtrack2026.2.18991 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| jetbrains youtrack | v < 2026.2.18991 | 2026.2.18991 |
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