CVE-2026-55521

High

Description

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits authorization checks in IndexesApi.listPacketIndex, IndexesApi.listEventIndex, Cop1Api.disable, Cop1Api.resume, Cop1Api.initialize, Cop1Api.updateConfig, and TimeApi.setTime. An authenticated low-privilege user can read packet and event index metadata without ObjectPrivilegeType.ReadPacket, alter COP-1 link state without SystemPrivilege.ControlLinks, and manipulate simulation time. These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability. This issue is fixed in versions 5.12.8 and 5.13.2.

SeverityHigh
CVSS8.8
Exploit probability—
ProductOrg.yamcs:yamcs-core
PublishedAug 28, 2026
First seenAug 28, 2026

How to fix

Update
  • org.yamcs:yamcs-core5.13.2, 5.12.8 or later

Affected products

ProductAffected versionsFixed in
org.yamcs:yamcs-coreMaven5.13.0 ≤ v < 5.13.2, v < 5.12.85.13.2, 5.12.8

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