Platform
azure
Component
himmelblau
Fixed in
2.0.1
3.0.1
CVE-2026-34397 describes a conditional local privilege escalation vulnerability found in Himmelblau IDM, an interoperability suite for Microsoft Azure Entra ID and Intune. This edge-case vulnerability allows authenticated users to potentially escalate their privileges on the system. The vulnerability impacts versions 2.0.0-alpha through 3.0.0-alpha, and 3.1.0. A fix is available in version 3.1.1.
An attacker exploiting this vulnerability could gain elevated privileges on a system running an affected version of Himmelblau IDM. This is achieved by leveraging a naming collision within the NSS module. If an authenticated user's mapped CN (Common Name) or short name exactly matches a privileged local group name (such as 'sudo', 'wheel', 'docker', or 'adm'), the NSS module may incorrectly resolve that group name to the user's fake primary group. Consequently, if the system relies on NSS results for group-based authorization decisions (e.g., sudo, polkit), the attacker could gain unauthorized access and execute commands with elevated privileges. The blast radius extends to any system where Himmelblau IDM is deployed and utilizes NSS for group authorization, potentially impacting critical infrastructure and sensitive data.
CVE-2026-34397 was published on 2026-04-01. There is no indication of active exploitation or a KEV listing at the time of writing. Public proof-of-concept code is currently unavailable. The vulnerability's reliance on a specific naming collision suggests that exploitation may require targeted reconnaissance and user account manipulation, potentially limiting its widespread impact.
Exploit Status
EPSS
0.01% (2% percentile)
CISA SSVC
CVSS Vector
The primary mitigation for CVE-2026-34397 is to upgrade Himmelblau IDM to version 3.1.1 or later. This version contains a fix that resolves the naming collision issue. If immediate upgrading is not feasible, consider implementing stricter naming conventions for user CNs and short names within Azure Entra ID to avoid collisions with privileged local group names. Review and audit group membership policies to ensure that users are not inadvertently assigned to privileged groups. While a direct WAF rule is unlikely, monitoring NSS module behavior for unexpected group resolutions could provide early detection. After upgrading, confirm the fix by attempting to escalate privileges with a user account whose CN/short name matches a privileged local group name; the escalation should fail.
Update Himmelblau to version 2.3.9 or later, or to version 3.1.1 or later, as appropriate for your version branch. This corrects the local privilege escalation vulnerability.
Vulnerability analysis and critical alerts directly to your inbox.
CVE-2026-34397 is a local privilege escalation vulnerability in Himmelblau IDM, allowing authenticated users to potentially gain elevated privileges through a naming collision.
You are affected if you are using Himmelblau IDM versions 2.0.0-alpha through 3.1.0 and your system relies on NSS for group-based authorization decisions.
Upgrade Himmelblau IDM to version 3.1.1 or later to remediate the vulnerability. Consider stricter naming conventions for user accounts as a temporary workaround.
There is currently no indication of active exploitation of CVE-2026-34397, but it is important to apply the patch promptly.
Refer to the official Himmelblau IDM security advisory for detailed information and updates regarding CVE-2026-34397.
Upload your dependency file and we'll tell you instantly if this and other CVEs hit you.