CVE-2026-55549 (GCVE-0-2026-55549)

Vulnerability from cvelistv5 – Published: 2026-08-28 17:15 – Updated: 2026-09-01 01:49
VLAI
Title
Yamcs: Reflected XSS in the URL of the Authorize Endpoint
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-01 01:48 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Impacted products
Vendor Product Version CPE status
yamcs yamcs Affected: < 5.9.4
guessed Create a notification for this product.
Show details on NVD website

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