CVE-2018-20021

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

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 2.64% Top 20%
Vendor Advisory debian.org Vendor Advisory ubuntu.com Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com Vendor Advisory ubuntu.com
Affected: n/a LibVNC
Published at:
Updated at:

References

Link Tags
https://www.debian.org/security/2019/dsa-4383 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html third party advisory mailing list
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/ third party advisory
https://usn.ubuntu.com/3877-1/ third party advisory vendor advisory
https://security.gentoo.org/glsa/201908-05 vendor advisory
https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html mailing list
https://lists.debian.org/debian-lts-announce/2019/11/msg00033.html mailing list
https://lists.debian.org/debian-lts-announce/2019/12/msg00028.html mailing list
https://security.gentoo.org/glsa/202006-06 vendor advisory
https://usn.ubuntu.com/4547-1/ vendor advisory
https://usn.ubuntu.com/4547-2/ vendor advisory
https://usn.ubuntu.com/4587-1/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-20021?
CVE-2018-20021 has been scored as a high severity vulnerability.
How to fix CVE-2018-20021?
To fix CVE-2018-20021, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-20021 being actively exploited in the wild?
It is possible that CVE-2018-20021 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-20021?
CVE-2018-20021 affects n/a LibVNC.
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