Rocky Linux 8 [CIQ] Security Update: libvncserver / libvncserver-debuginfo / libvncserver-debugsource / etc Multiple Vulnerabilities (crlsa-2021_1811)

high Nessus Plugin ID 357597

Synopsis

The Rocky Linux host is missing one or more security updates.

Description

The Rocky Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the CIQ crlsa-2021_1811 advisory.

* libvncserver: uninitialized memory contents are vulnerable to Information Leak (CVE-2018-21247)

* libvncserver: buffer overflow in ConnectClientToUnixSock() (CVE-2019-20839)

* libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference (CVE-2020-14397)

* libvncserver: libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405)

* libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS (CVE-2020-25708)

Tenable has extracted the preceding description block directly from the CIQ 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 based on the guidance in CIQ advisory crlsa-2021_1811.

Plugin Details

Severity: High

ID: 357597

File Name: ciq_rocky_linux_8_crlsa-2021_1811.nasl

Version: 1.1

Type: Local

Family: Rocky Linux Local Security Checks

Published: 10/1/2026

Updated: 10/1/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.18

Vendor

Vendor Severity: Unknown

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.9

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

CVSS Score Source: CVE-2018-21247

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.7

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:P/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/RockyLinux/release, Host/RockyLinux/rpm-list, Host/OS/extended-third-party

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/18/2021

Vulnerability Publication Date: 6/17/2020

Reference Information

CVE: CVE-2018-21247, CVE-2019-20839, CVE-2020-14397, CVE-2020-14405, CVE-2020-25708

Detections

Analytics