Alibaba Cloud Linux 3 : 0011: stunnel (ALINUX3-SA-2021:0011)

high Nessus Plugin ID 236598

Synopsis

The remote Alibaba Cloud Linux host is missing one or more security updates.

Description

The remote Alibaba Cloud Linux 3 host has packages installed that are affected by a vulnerability as referenced in the ALINUX3-SA-2021:0011 advisory.

Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

CVE-2021-20230:
A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality.

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

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

Solution

Update the affected stunnel, stunnel-debuginfo and / or stunnel-debugsource packages.

Plugin Details

Severity: High

ID: 236598

File Name: alinux3_sa_2021-0011.nasl

Version: 1.1

Type: local

Family: Alibaba Cloud Linux Local Security Checks

Published: 5/14/2025

Updated: 5/14/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2021-20230

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:H/I:N/A:N

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

Vulnerability Information

CPE: p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:stunnel-debugsource, cpe:/o:alibabacloud:alibaba_cloud_linux_3, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:stunnel-debuginfo, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:stunnel

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/Alibaba/release, Host/Alibaba/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 2/25/2021

Vulnerability Publication Date: 2/22/2021

Reference Information

CVE: CVE-2021-20230

Detections

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