6.5
MEDIUM CVSS 3.1
CVE-2026-55545
Yamcs: WebSocket subscription handlers omit the privilege checks their REST siblings enforce
Description

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.

INFO

Published Date :

Aug. 28, 2026, 8:18 p.m.

Last Modified :

Aug. 28, 2026, 8:18 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55545 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update Yamcs to versions 5.12.8 or 5.13.2 to enforce privilege checks.
  • Update Yamcs to version 5.12.8 or later.
  • Verify privilege checks on WebSocket topics.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55545 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-55545 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55545 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55545 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-862
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/55xxx/CVE-2026-55545.json">CVE-2026-55545</a>
    Added Reference https://github.com/yamcs/yamcs/commit/0691731846c5a0aca81b88fabbd2cd51d56fe076
    Added Reference https://github.com/yamcs/yamcs/commit/12864af555e6ca4941b01c1f1217859cc0492ce0
    Added Reference https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8
    Added Reference https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2
    Added Reference https://github.com/yamcs/yamcs/security/advisories/GHSA-fwww-cp23-7f5g
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.