CVE Intelligence
Medium Access control

CVE-2025-59044 — Himmelblau vulnerable to GID collision via group name-derived mapping (privilege escalation)

Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. Himmelblau 0.9.x derives numeric GIDs for Entra ID groups from the group display name when himmelblau.conf `id_attr_map = name` (the default configuration). Because Microsoft Entra ID allows multiple groups with the same `displayName` (including end-user–created personal/O365 groups, depending on tenant policy), distinct directory groups can collapse to the same numeric GID on Linux. This issue only applies to Himmelblau versions 0.9.0 through 0.9.22. Any resource or service on a Himmelblau-joined host that enforces authorization by numeric GID (files/dirs, etc.) can be unintentionally accessible to a user who creates or joins a different Entra/O365 group that happens to share the same `displayName` as a privileged security group. Users should upgrade to 0.9.23, or 1.0.0 or later, to receive a patch. Group to GID mapping now uses Entra ID object IDs (GUIDs) and does not collide on same-name groups. As a workaround, use tenant policy hardening to restrict arbitrary group creation until all hosts are patched.

Published Sep 9, 2025 · Updated Oct 19, 2026 · Sources: CVE Program (cve.org) e CISA ADP, NIST National Vulnerability Database · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.1% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.15%
ahead of 3% of scored CVEs · Oct 19, 2026
Affects
Himmelblau-idm
Himmelblau
CVSS base
4.4
Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Himmelblau-idm Himmelblau).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (access control), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Himmelblau-idm Himmelblau version >= 0.9.0, < 0.9.23 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
4.4 CVSS 3.1 Medium 1.8 2.5 security-advisories@github.com via NIST National Vulnerability Database
4.4 CVSS 3.1 Medium — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-1188 · Insecure Default Initialization of Resource

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
  • Audit administrative actions and access to resources outside each user’s normal pattern.
endpoint telemetry (EDR)authentication logsapplication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Source status changed · Published → Deferred
    Oct 19, 2026 · NIST National Vulnerability Database
  • Record published
    Oct 19, 2026
  • Affected products added · himmelblau-idm/himmelblau
    Oct 19, 2026 · CVE Program (cve.org) e CISA ADP
  • CVSS changed · 4.4
    Oct 19, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Published
    Oct 19, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 19, 2026 · CVE Program (cve.org) e CISA ADP
  • Record created in this database
    Oct 19, 2026 · Alertas do Telegram
  • 2025
  • CVE published
    Sep 9, 2025 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 19, 2026 – Oct 19, 2026
  • 1× Official description updated · Oct 19, 2026 – Oct 19, 2026

References

3 on the record

Elsewhere on this site

Himmelblau-idm
every CVE for this vendor
Access control
same class
CWE-1188
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-45108 Himmelblau: Authentication Bypass via Cross-User Local Session Impersonation in Device Authorization Grant (DAG) Flow May 27, 2026
  • CVE-2026-34397 himmelblau: NSS fake-primary group lookup reintroduces name collision risk Apr 1, 2026
  • CVE-2026-31979 himmelblaud-tasks: local privilege escalation via /tmp symlink attack on Kerberos ccache Mar 11, 2026
  • CVE-2026-31957 Himmelblau unset domain configuration can allow any-tenant authentication at first login for remote deployments Mar 11, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-59044 is "Himmelblau vulnerable to GID collision via group name-derived mapping (privilege escalation)", rated Medium. It affects Himmelblau (Himmelblau-idm); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.4 describes technical severity. EPSS 0.15% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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