CVE-2026-55549

Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirect_uri parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java and yamcs-core/src/main/java/org/yamcs/http/HandlerContext.java. A crafted authorization URL can execute JavaScript when opened by a Yamcs user. The script can access browser-held authentication material and transmit it to an attacker, enabling account compromise. This issue is fixed in version 5.9.4.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/yamcs/yamcs/commit/4d47d5cdcf5d92c2c5bbbc19feada422923332e3
https://github.com/yamcs/yamcs/releases/tag/yamcs-5.9.4
https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c
https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 20:18

Updated : 2026-09-08 21:08

NVD link : CVE-2026-55549

Mitre link : CVE-2026-55549

CVE.ORG link : CVE-2026-55549

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

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