Oracle Linux 7 : tigervnc (ELSA-2020-3875)

high Nessus Plugin ID 141215

Synopsis

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

Description

The remote Oracle Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2020-3875 advisory.

- TigerVNC version prior to 1.10.1 is vulnerable to stack use-after-return, which occurs due to incorrect usage of stack memory in ZRLEDecoder. If decoding routine would throw an exception, ZRLEDecoder may try to access stack variable, which has been already freed during the process of stack unwinding. Exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity. (CVE-2019-15691)

- TigerVNC version prior to 1.10.1 is vulnerable to heap buffer overflow. Vulnerability could be triggered from CopyRectDecoder due to incorrect value checks. Exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity.
(CVE-2019-15692)

- TigerVNC version prior to 1.10.1 is vulnerable to heap buffer overflow, which occurs in TightDecoder::FilterGradient. Exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity. (CVE-2019-15693)

- TigerVNC version prior to 1.10.1 is vulnerable to heap buffer overflow, which could be triggered from DecodeManager::decodeRect. Vulnerability occurs due to the signdness error in processing MemOutStream.
Exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity. (CVE-2019-15694)

- TigerVNC version prior to 1.10.1 is vulnerable to stack buffer overflow, which could be triggered from CMsgReader::readSetCursor. This vulnerability occurs due to insufficient sanitization of PixelFormat.
Since remote attacker can choose offset from start of the buffer to start writing his values, exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity. (CVE-2019-15695)

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 packages.

See Also

http://linux.oracle.com/errata/ELSA-2020-3875.html

Plugin Details

Severity: High

ID: 141215

File Name: oraclelinux_ELSA-2020-3875.nasl

Version: 1.4

Type: local

Agent: unix

Published: 10/7/2020

Updated: 2/16/2024

Supported Sensors: Frictionless Assessment Agent, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.1

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

CVSS Score Source: CVE-2019-15695

CVSS v3

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: cpe:/o:oracle:linux:7, p-cpe:/a:oracle:linux:tigervnc, p-cpe:/a:oracle:linux:tigervnc-icons, p-cpe:/a:oracle:linux:tigervnc-license, p-cpe:/a:oracle:linux:tigervnc-server, p-cpe:/a:oracle:linux:tigervnc-server-applet, p-cpe:/a:oracle:linux:tigervnc-server-minimal, p-cpe:/a:oracle:linux:tigervnc-server-module

Required KB Items: Host/OracleLinux, Host/RedHat/release, Host/RedHat/rpm-list, Host/local_checks_enabled

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/6/2020

Vulnerability Publication Date: 12/26/2019

Reference Information

CVE: CVE-2019-15691, CVE-2019-15692, CVE-2019-15693, CVE-2019-15694, CVE-2019-15695