Answer in brief
CVE-2026-55545 records a Medium severity (CVSS 6.5) vulnerability in Yamcs: WebSocket subscription handlers omit the privilege checks their REST siblings enforce. The current sources do not mark it as known exploited. The current feed maps yamcs/yamcs (generic), org.yamcs:yamcs-core (maven), org.yamcs:yamcs-core (maven). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps yamcs/yamcs (generic), org.yamcs:yamcs-core (maven), org.yamcs:yamcs-core (maven). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| yamcs/yamcsgeneric | < 5.12.8 || >= 5.13.0, < 5.13.2 | Not reported |
| org.yamcs:yamcs-coremaven | <=5.12.7 | 5.12.8 |
| org.yamcs:yamcs-coremaven | >=5.13.0,<=5.13.1 | 5.13.2 |
Published upstream
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 28, 2026
Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket, ProcessingApi.subscribeAlgorithmStatus exposes the algorithm-status WebSocket topic without ObjectPrivilegeType.ReadAlgorithm, and MdbOverrideApi.subscribeMdbChanges exposes the mdb-changes WebSocket topic without SystemPrivilege.GetMissionDatabase. A low-privilege authenticated user can receive telemetry packets, algorithm status, and mission database change information outside the assigned authorization scope. This issue is fixed in versions 5.12.8 and 5.13.2.
Quoted source text, attributed separately from HOL analysis.