4.3
MEDIUM CVSS 3.1
CVE-2026-55547
Yamcs: Missing Authorization on Role and Privilege Enumeration Endpoints Allows Any Authenticated User to Disclose Full Security Configuration
Description

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits SystemPrivilege.ControlAccess checks from IamApi.listRoles, IamApi.getRole, and IamApi.listPrivileges in yamcs-core/src/main/java/org/yamcs/http/api/IamApi.java. Any authenticated account can call GET /api/roles, GET /api/roles/{name}, and GET /api/privileges to enumerate available system privileges and configured role mappings. The disclosure reveals security configuration that can support targeted privilege-escalation attempts. 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, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55547 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 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update Yamcs to a patched version to address authorization bypass in role enumeration.
  • Update Yamcs to version 5.12.8 or later.
  • Update Yamcs to version 5.13.2 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55547 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-2026-55547 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-2026-55547 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55547 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.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/yamcs/yamcs/security/advisories/GHSA-cvw4-55pp-3hfq
    Added SSVC {'id': 'CVE-2026-55547', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-28T20:29:51.716854Z'}
  • 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 omits SystemPrivilege.ControlAccess checks from IamApi.listRoles, IamApi.getRole, and IamApi.listPrivileges in yamcs-core/src/main/java/org/yamcs/http/api/IamApi.java. Any authenticated account can call GET /api/roles, GET /api/roles/{name}, and GET /api/privileges to enumerate available system privileges and configured role mappings. The disclosure reveals security configuration that can support targeted privilege-escalation attempts. 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:L/I:N/A:N
    Added CWE CWE-285
    Added CWE CWE-862
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/55xxx/CVE-2026-55547.json">CVE-2026-55547</a>
    Added Reference https://github.com/yamcs/yamcs/commit/c2aec1c242e656e48b52c7f87deea88183bb592d
    Added Reference https://github.com/yamcs/yamcs/commit/dcaec5f0b2f4231b8e313e94d79a937169c9e0ba
    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-cvw4-55pp-3hfq
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.