High 8.8Published Aug 28, 2026

CVE-2026-55521Yamcs : Multiple Missing Function Level Access Control vulnerabilities in Yamcs Core API

Updated under an hour ago (2026-10-19 08:30 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for yamcs

Exploited in the last 30 days

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.

CVSS: 8.8 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-862
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Awaiting Analysis
Record last updated: Aug 28, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

yamcs yamcs yamcs:yamcs (from the name)	before 5.12.8; from 5.13.0, < 5.13.2	CNA record

References

https://github.com/yamcs/yamcs/security/advisories/GHSA-962x-ccwf-8x6px-refsource-confirm
https://github.com/yamcs/yamcs/commit/405139afa6094dfaf63ac17f32df1f808846c950x-refsource-misc
https://github.com/yamcs/yamcs/commit/493563679f838b86f3cdc5da9451d4a050ff6bd9x-refsource-misc
https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8x-refsource-misc
https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.