Detections
Analytics
TencentOS Server 4: microcode_ctl (TSSA-2026:0851)
high Nessus Plugin ID 339168
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-2026:0851 advisory.Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:
CVE-2026-20713:
Always-incorrect control flow implementation in some firmware for some Intel(R) Xeon(R) processors may allow an escalation of privilege. System software adversary with a privileged user combined with a high complexity attack may enable escalation of privilege. This result may potentially occur via local access when attack requirements are not present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (none) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (high), integrity (high) and availability (none) impacts.
CVE-2026-20707:
Hardware logic contains race conditions for some 3rd Gen Intel(R) Xeon(R) Scalable Processors within Ring 3: unprivileged software may allow a denial of service.
CVE-2025-31936:
Improper handling of overlap between protected memory ranges for some Intel(R) Xeon(R) 6 processors when using Intel(R) TDX within SMM may allow an escalation of privilege. SMM adversary with a privileged user combined with a high complexity attack may enable escalation of privilege. This result may potentially occur via local access when attack requirements are present with special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (high), integrity (high) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.
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
Plugin Details
Severity: High
ID: 339168
File Name: tencentos_TSSA_2026_0851.nasl
Version: 1.1
Type: Local
Family: Tencent Local Security Checks
Published: 8/25/2026
Updated: 8/25/2026
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.8
Percentile: 57.84
CVSS v2
Risk Factor: Medium
Base Score: 5.3
Temporal Score: 3.9
Vector: CVSS2#AV:L/AC:H/Au:M/C:C/I:C/A:N
CVSS Score Source: CVE-2026-20713
CVSS v3
Risk Factor: High
Base Score: 7.2
Temporal Score: 6.3
Vector: CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
CVSS v4
Risk Factor: High
Base Score: 7
Threat Score: 3.7
Threat Vector: CVSS:4.0/E:U
Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CVSS Score Source: CVE-2025-31936
Vulnerability Information
CPE: cpe:/o:tencent:tencentos_server:4, p-cpe:/a:tencent:tencentos_server:microcode_ctl
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: 8/18/2026
Vulnerability Publication Date: 8/11/2026