CVE-2026-31979 (GCVE-0-2026-31979)

Vulnerability from cvelistv5 – Published: 2026-03-11 19:47 – Updated: 2026-03-11 20:07
VLAI
Title
himmelblaud-tasks: local privilege escalation via /tmp symlink attack on Kerberos ccache
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.
Severity
8.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-11 20:07 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
himmelblau-idm himmelblau Affected: >= 1.0.0, < 2.3.8
Affected: >= 3.0.0-alpha, < 3.1.0
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