Detections
Analytics
TencentOS Server 4: python-pyasn1 (TSSA-2026:1349)
high Nessus Plugin ID 377888
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-2026:1349 advisory.Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:
CVE-2026-119197:
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, binary REAL decoding builds a large mantissa one octet at a time by shifting a growing integer and slicing the remaining byte string. Attacker- controlled ASN.1 includes a binary-encoded REAL with a large mantissa and reaches BER, CER, or DER decode(), with or without a schema containing REAL. RealPayloadDecoder.valueDecoder repeatedly performs a left shift, OR, and suffix copy for every mantissa octet, making decode time quadratic in mantissa length.
A comparatively small REAL value can hold a decoding worker on one CPU core for seconds or longer and cause availability loss. This issue is fixed in version 0.6.5.
CVE-2026-119196:
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, constructed BIT STRING decoding repeatedly shifts and copies the complete bit value accumulated from earlier fragments. Attacker-controlled BER or CER input contains many constructed BIT STRING fragments; schema-driven DER also accepts a definite-length constructed BIT STRING. BitStringPayloadDecoder repeatedly calls BitString.fromOctetString with the prior bitString as prepend, shifting an ever-growing SizedInteger for each fragment and causing quadratic work.
Large fragmented values can exhaust CPU during decode() without requiring later conversion or formatting.
This issue is fixed in version 0.6.5.
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: 377888
File Name: tencentos_TSSA_2026_1349.nasl
Version: 1.1
Type: Local
Family: Tencent Local Security Checks
Published: 11/9/2026
Updated: 11/9/2026
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Low
Score: 3
Percentile: 23.74
CVSS v2
Risk Factor: High
Base Score: 7.8
Temporal Score: 5.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS Score Source: CVE-2026-119197
CVSS v3
Risk Factor: High
Base Score: 7.5
Temporal Score: 6.5
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:python-pyasn1
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: 11/5/2026
Vulnerability Publication Date: 10/29/2026