Is CVE-2018-20749 in the CISA KEV catalog?

No. CVE-2018-20749 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2018-20749?

CVE-2018-20749 has a CVSS v3 base score of 9.8 (CRITICAL).

What is the EPSS score for CVE-2018-20749?

CVE-2018-20749 has an EPSS score of 3.23% (87th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2018-20749?

Upgrade libvncserver on debian 11 to 0.9.11+dfsg-1.3 or later. Fixes are available for 9 affected products.

CVE & CISA-KEV Catalog

CVE-2018-20749

CRITICALEPSS 87th pctl

9.8

CVSS v3

NVD

Description

LibVNC before 0.9.12 contains a heap out-of-bounds write vulnerability in libvncserver/rfbserver.c. The fix for CVE-2018-15127 was incomplete.

CWE-787Out-of-bounds Write

How to fix

Remediation Available

libvncserverDebian

Fixed in:0.9.11+dfsg-1.3CVE-2018-20749

italcUbuntu

Fixed in:1:2.0.2+dfsg1-4ubuntu0.1USN-4587-1

Fixed in:1:3.0.3+dfsg1-3ubuntu0.1USN-4547-1

italc-clientUbuntu

Fixed in:1:2.0.2+dfsg1-4ubuntu0.1USN-4587-1

Fixed in:1:3.0.3+dfsg1-3ubuntu0.1USN-4547-1

italc-masterUbuntu

Fixed in:1:2.0.2+dfsg1-4ubuntu0.1USN-4587-1

Fixed in:1:3.0.3+dfsg1-3ubuntu0.1USN-4547-1

libitalccoreUbuntu

Fixed in:1:2.0.2+dfsg1-4ubuntu0.1USN-4587-1

Fixed in:1:3.0.3+dfsg1-3ubuntu0.1USN-4547-1

libvncclient1Ubuntu

Fixed in:0.9.10+dfsg-3ubuntu0.16.04.3USN-3877-1

Fixed in:0.9.11+dfsg-1ubuntu1.1USN-3877-1

libvncserverUbuntu

Fixed in:0.9.9+dfsg-1ubuntu1.4USN-3877-1

Fixed in:0.9.10+dfsg-3ubuntu0.16.04.3USN-3877-1

Fixed in:0.9.11+dfsg-1ubuntu1.1USN-3877-1

libvncserver0Ubuntu

Fixed in:0.9.9+dfsg-1ubuntu1.4USN-3877-1

libvncserver1Ubuntu

Fixed in:0.9.10+dfsg-3ubuntu0.16.04.3USN-3877-1

Fixed in:0.9.11+dfsg-1ubuntu1.1USN-3877-1

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

3.23%probability of exploitation in 30 days

87thpercentile

Elevated risk: more likely to be exploited than 87% of all known CVEs.

References

Patch2

Exploit1

openwall.com

Third-Party Advisory6

Other references1

securityfocus.com

Related Vulnerabilities

Other CWE-787 (Out-of-bounds Write) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2025-22457	Critical	9.0	100%	KEV + Ransom	Fix
CVE-2025-0282	Critical	9.0	100%	KEV + Ransom	-
CVE-2015-3113	Critical	9.8	100%	KEV	Fix
CVE-2021-20038	Critical	9.8	100%	KEV + Ransom	-
CVE-2023-4863	High	8.8	100%	KEV	Fix
CVE-2020-16040	Medium	6.5	100%	-	Fix

Embed a live status badge for CVE-2018-20749

Markdown

[![CVE-2018-20749](https://tridentstack.com/cve/badge/CVE-2018-20749.svg)](https://tridentstack.com/cve/CVE-2018-20749)

HTML

<a href="https://tridentstack.com/cve/CVE-2018-20749"><img src="https://tridentstack.com/cve/badge/CVE-2018-20749.svg" alt="CVE-2018-20749"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.