TencentOS Server 4: libvirt (TSSA-2026:0978)

high Nessus Plugin ID 344405

Synopsis

The remote TencentOS Server 4 host is missing one or more security updates.

Description

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0978 advisory.

Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

CVE-2026-63623:
A flaw was found in libvirt. During storage volume clone or convert operations, newly created volume images were temporarily world-readable. This was caused by the qemu-img utility running with overly permissive file creation settings, allowing any local user to read the full guest disk contents. This vulnerability could lead to sensitive information disclosure from guest virtual machines.

CVE-2026-63622:
A flaw was found in libvirt. A local attacker, specifically a process running as the confined swtpm user, could exploit a symlink-following vulnerability in the virFileChownFiles() function. By planting a symbolic link within the swtpm state directory, the attacker could trick the root-level libvirt daemon into changing the ownership of an arbitrary file to the swtpm user. This allows for privilege escalation from the swtpm sandbox to root-level file ownership control.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://mirrors.tencent.com/tlinux/errata/tssa-20260978.xml

Plugin Details

Severity: High

ID: 344405

File Name: tencentos_TSSA_2026_0978.nasl

Version: 1.1

Type: Local

Published: 9/9/2026

Updated: 9/9/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.18

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-63622

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:tencent:tencentos_server:4, p-cpe:/a:tencent:tencentos_server:libvirt

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/etc/os-release, Host/TencentOS/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 9/8/2026

Vulnerability Publication Date: 8/10/2026

Reference Information

CVE: CVE-2026-63622, CVE-2026-63623