CVE-2026-77159

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-77159
https://bugzilla.redhat.com/show_bug.cgi?id=2531811
https://gitlab.com/libvirt/libvirt/-/work_items/909
https://gitlab.com/libvirt/libvirt/-/work_items/909

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 11:16

Updated : 2026-09-15 16:17

NVD link : CVE-2026-77159

Mitre link : CVE-2026-77159

CVE.ORG link : CVE-2026-77159

JSON object : View

Products Affected

No product.

CWE

CWE-61

UNIX Symbolic Link (Symlink) Following

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