7.5
HIGH
CVE-2018-20021
LibVNC Infinite Loop Vulnerability
Description

LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM

INFO

Published Date :

Dec. 19, 2018, 4:29 p.m.

Last Modified :

Oct. 23, 2020, 1:15 p.m.

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2018-20021 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Canonical ubuntu_linux
1 Debian debian_linux
1 Libvnc_project libvncserver

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2018-20021 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2018-20021 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Oct. 23, 2020

    Action Type Old Value New Value
    Added Reference https://usn.ubuntu.com/4587-1/ [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 05, 2020

    Action Type Old Value New Value
    Added Reference https://usn.ubuntu.com/4547-2/ [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 30, 2020

    Action Type Old Value New Value
    Added Reference https://usn.ubuntu.com/4547-1/ [No Types Assigned]
  • CVE Modified by [email protected]

    Jun. 13, 2020

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/202006-06 [No Types Assigned]
  • CVE Modified by [email protected]

    Dec. 21, 2019

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2019/12/msg00028.html [No Types Assigned]
  • CVE Modified by [email protected]

    Nov. 29, 2019

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2019/11/msg00033.html [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 31, 2019

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html [No Types Assigned]
  • CWE Remap by [email protected]

    Oct. 03, 2019

    Action Type Old Value New Value
    Changed CWE CWE-400 CWE-400 CWE-399 CWE-835
  • CVE Modified by [email protected]

    Aug. 09, 2019

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/201908-05 [No Types Assigned]
  • Modified Analysis by [email protected]

    Feb. 26, 2019

    Action Type Old Value New Value
    Changed Reference Type https://usn.ubuntu.com/3877-1/ No Types Assigned https://usn.ubuntu.com/3877-1/ Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2019/dsa-4383 No Types Assigned https://www.debian.org/security/2019/dsa-4383 Third Party Advisory
    Changed CPE Configuration OR *cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* OR *cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Feb. 04, 2019

    Action Type Old Value New Value
    Added Reference https://www.debian.org/security/2019/dsa-4383 [No Types Assigned]
  • CVE Modified by [email protected]

    Feb. 01, 2019

    Action Type Old Value New Value
    Added Reference https://usn.ubuntu.com/3877-1/ [No Types Assigned]
  • Initial Analysis by [email protected]

    Jan. 07, 2019

    Action Type Old Value New Value
    Added CVSS V2 (AV:N/AC:L/Au:N/C:N/I:N/A:C)
    Added CVSS V3 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/ No Types Assigned https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/ Third Party Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html No Types Assigned https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html Mailing List, Third Party Advisory
    Added CWE CWE-400
    Added CPE Configuration OR *cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:* versions up to (excluding) 0.9.12
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Dec. 27, 2018

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html [No Types Assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2018-20021 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2018-20021 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.96 }} -0.09%

score

0.83408

percentile

CVSS30 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability