Yamcs: Unauthorized user enumeration via IAM API endpoints (CVE-2026-44595) | HOL Guard CVE

Medium · CVSS 4.3CVE-2026-44595

Yamcs: Unauthorized user enumeration via IAM API endpoints

Answer in brief

CVE-2026-44595 records a Medium severity (CVSS 4.3) vulnerability in Yamcs: Unauthorized user enumeration via IAM API endpoints. The current sources do not mark it as known exploited. The current feed maps yamcs/yamcs (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 16, 2026Updated Jul 18, 2026Source checked Sep 19, 2026First seen by HOL Jul 16, 2026Material review Jul 18, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 4.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps yamcs/yamcs (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
yamcs/yamcsgeneric	< 5.12.7	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for yamcs/yamcs.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Jul 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Jul 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jul 16, 2026

Sources and claim methodology

Upstream source description

Yamcs is a mission control framework. Prior to 5.12.7, the IAM API endpoints listUsers, getUser, listGroups, and getGroup in yamcs-core did not enforce the required SystemPrivilege.ControlAccess check in yamcs-core/src/main/java/org/yamcs/http/api/IamApi.java, so any authenticated user, even one with low or no privileges, could enumerate all user accounts in the system including their usernames, superuser status, and group memberships. This issue is fixed in versions 5.12.7 and 5.13.0.

Quoted source text, attributed separately from HOL analysis.