CVE-2026-55521CWE-862broken-access-control

CVE-2026-55521

High · published August 29, 2026

CVSS v3.1
8.8
EPSS
1%
Percentile
43.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00523 · 43.5th percentile
Weakness
CWE-862 · Missing Authorization
Published
2026-08-29T00:18Z
References (6)
EPSS history
Timeline
  • 30 AUG 16:18Z
    EPSS moved — → 0%
    epss
  • 28 AUG 17:08Z
    Yamcs : Multiple Missing Function Level Access Control vulnerabilities in Yamcs Core API
    cvelistv5