SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-55521

These operations can disclose telemetry metadata, disrupt telecommand handling, and affect system integrity and availability.

HIGH 8.8EPSS 0.36%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.36% probability · 29th percentile
CISA KEV
Not listed
Weakness
CWE-862
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.