CVE-2026-31979

Summary

Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. Prior to 3.1.0 and 2.3.8, the himmelblaud-tasks daemon, running as root, writes Kerberos cache files under /tmp/krb5cc_<uid> without symlink protections. Since commit 87a51ee, PrivateTmp is explicitly removed from the tasks daemon's systemd hardening, exposing it to the host /tmp. A local user can exploit this via symlink attacks to chown or overwrite arbitrary files, achieving local privilege escalation. This vulnerability is fixed in 3.1.0 and 2.3.8.

Affected Software

VendorProductVersion RangeStatus
himmelblau-idmhimmelblau>= 1.0.0, < 2.3.8affected
himmelblau-idmhimmelblau>= 3.0.0-alpha, < 3.1.0affected

Weaknesses

  • CWE-59: CWE-59: Improper Link Resolution Before File Access ('Link Following')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: total

References