EulerOS 2.0 SP8 : tigervnc (EulerOS-SA-2020-1885)

high Nessus Plugin ID 139988
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote EulerOS host is missing multiple security updates.

Description

According to the versions of the tigervnc packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

- 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 Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Solution

Update the affected tigervnc packages.

See Also

http://www.nessus.org/u?cdb5dbce

Plugin Details

Severity: High

ID: 139988

File Name: EulerOS_SA-2020-1885.nasl

Version: 1.4

Type: local

Published: 8/28/2020

Updated: 1/6/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 4.8

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.3

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

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

Vulnerability Information

CPE: p-cpe:/a:huawei:euleros:tigervnc, p-cpe:/a:huawei:euleros:tigervnc-icons, p-cpe:/a:huawei:euleros:tigervnc-license, p-cpe:/a:huawei:euleros:tigervnc-server, p-cpe:/a:huawei:euleros:tigervnc-server-minimal, cpe:/o:huawei:euleros:2.0

Required KB Items: Host/local_checks_enabled, Host/EulerOS/release, Host/EulerOS/rpm-list, Host/EulerOS/sp

Excluded KB Items: Host/EulerOS/uvp_version

Exploit Ease: No known exploits are available

Patch Publication Date: 8/28/2020

Reference Information

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