CVE-2026-34397 json
himmelblau: NSS fake-primary group lookup reintroduces name collision risk
published 7mo ago modified 4mo ago also EUVD-2026-17983
- cvss
- 6.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 5%
- public exploits
- 0
- none known
Summary
Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From versions 2.0.0-alpha to before 2.3.9 and 3.0.0-alpha to before 3.1.1, there is a conditional local privilege escalation vulnerability in an edge-case naming collision. Only authenticated himmelblau users whose mapped CN/short name exactly matches a privileged local group name (e.g., "sudo", "wheel", "docker", "adm") can cause the NSS module to resolve that group name to their fake primary group. If the system uses NSS results for group-based authorization decisions (sudo, polkit, etc.), this can grant the attacker the privileges of that group. This issue has been patched in versions 2.3.9 and 3.1.1.
Patch / fix
- himmelblau-idm himmelblau 2.3.9, 3.1.1
- himmelblau SLE Module for Basesystem 15 SP7 2.3.9+git0.a9fd29b-150700.3.15.1
suse advisories SUSE-SU-2026:1361-1
- himmelblau openSUSE Tumbleweed 2.3.9+git0.a9fd29b-1.1
opensuse advisories openSUSE-SU-2026:10483-1
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 7mo ago
Exploit prediction
0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/himmelblau-idm/himmelblau/security/advisories/GHSA-v7xx-7mqc-g835 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.3 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N |
| NVD | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- himmelblau-idm himmelblau
Classification
- Weakness
-
- CWE-269 Improper Privilege Management
References
-
github.com
/himmelblau-idm/himmelblau/security/advisories/GHSA-v7xx-7mqc-g835
exploit, mitigation, vendor-advisory
-
github.com
/himmelblau-idm/himmelblau/releases/tag/2.3.9
product, release-notes
-
github.com
/himmelblau-idm/himmelblau/releases/tag/3.1.1
product, release-notes
Sources
- CVE List CVE-2026-34397
- NVD CVE-2026-34397
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.