CVE-2026-100263

In JetBrains YouTrack before 2026.2.18991 stored HTML injection via the User-Agent header was possible

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://www.jetbrains.com/privacy-security/issues-fixed/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:jetbrains:youtrack:*:*:*:*:*:*:*:*

History

02 Oct 2026, 20:23

Type	Values Removed	Values Added
CPE		cpe:2.3:a:jetbrains:youtrack::::::::
References	~~() https://www.jetbrains.com/privacy-security/issues-fixed/ -~~	() https://www.jetbrains.com/privacy-security/issues-fixed/ - Vendor Advisory
First Time		Jetbrains Jetbrains youtrack

30 Sep 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 16:16

Updated : 2026-10-02 20:23

NVD link : CVE-2026-100263

Mitre link : CVE-2026-100263

CVE.ORG link : CVE-2026-100263

JSON object : View

Products Affected

jetbrains

youtrack

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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