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{"acknowledgement": "Red Hat would like to thank Suraj Theekshana for reporting this issue.", "bugzilla": {"description": "libvirt: Unsafe chown in qemuTPMEmulatorPrepareHost() allows arbitrary file ownership change via symlink", "id": "2531811", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531811"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N", "status": "draft"}, "cwe": "CWE-61", "details": ["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."], "mitigation": {"lang": "en:us", "value": "On Red Hat Enterprise Linux, SELinux in enforcing mode (the default) confines the swtpm process to the swtpm_t domain, which restricts the creation of symlinks to arbitrary file types and limits the scope of any ownership change, reducing the practical impact of this flaw. Ensure SELinux is not disabled or set to permissive mode."}, "name": "CVE-2026-77159", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "libvirt", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "libvirt", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "libvirt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "virt:rhel/libvirt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "libvirt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-09-11T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-77159\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-77159\nhttps://gitlab.com/libvirt/libvirt/-/work_items/909"], "threat_severity": "Moderate"}