CVE-2026-77159 (GCVE-0-2026-77159)

Vulnerability from cvelistv5 – Published: 2026-09-11 10:32 – Updated: 2026-09-15 15:40
VLAI
Title
Libvirt: unsafe chown in qemutpmemulatorpreparehost() allows arbitrary file ownership change via symlink
Summary
A symlink-following flaw was found in libvirt's qemuTPMEmulatorPrepareHost() function. The function uses a path-based chown() on the swtpm logfile without checking for symbolic links. A local attacker with access to the swtpm account can replace the logfile with a symlink, causing libvirtd (running as root) to transfer ownership of an arbitrary file to the swtpm user.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 15:39 UTC
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
References
Impacted products
Date Public
2026-09-11 00:00
Credits
Red Hat would like to thank Suraj Theekshana for reporting this issue.
Show details on NVD website
To clipboard 

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