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

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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