CVE & CISA-KEV Catalog

CVE-2020-11868

HIGHEPSS 81th pctl

7.5

CVSS v3

Description

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address, because transmissions are rescheduled even when a packet lacks a valid origin timestamp.

How to fix

Remediation Available

ntpAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

ntp-debuginfoAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

ntp-docAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

ntp-perlAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

ntpdateAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

sntpAmazon

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

Fixed in:0:4.2.6p5-29.amzn2.0.2

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

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

ConfidentialityNone

IntegrityNone

AvailabilityHigh

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

Exploit Intelligence

2.13%probability of exploitation in 30 days

81stpercentile

Elevated risk: more likely to be exploited than 81% of all known CVEs.

References

Patch2

Third-Party Advisory6

Related Vulnerabilities

Other CWE-346 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2025-34291	High	8.8	84%	KEV	-
CVE-2009-1185	High	7.2	82%	-	Fix
CVE-2015-4495	High	8.8	71%	KEV	Fix
CVE-2020-16952	High	8.6	71%	-	-
CVE-2023-29711	Critical	9.8	70%	-	-
CVE-2024-23898	High	8.8	67%	-	Fix

Common questions

How do I fix CVE-2020-11868?

Published advisories record a fix for 6 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2020-11868 being actively exploited?

Not that we know of. CVE-2020-11868 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 2.1% is the estimated probability that it will be exploited in the next 30 days. That is higher than 81% of all scored CVEs.

How severe is CVE-2020-11868?

CVE-2020-11868 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2020-11868 affect?

Published advisories record a fix for ntp (Amazon), ntp-debuginfo (Amazon), ntp-doc (Amazon), ntp-perl (Amazon), and 2 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2020-11868

Markdown

[![CVE-2020-11868](https://tridentstack.com/cve/badge/CVE-2020-11868.svg)](https://tridentstack.com/cve/CVE-2020-11868)

HTML

<a href="https://tridentstack.com/cve/CVE-2020-11868"><img src="https://tridentstack.com/cve/badge/CVE-2020-11868.svg" alt="CVE-2020-11868"></a>

Check your Linux endpoints for this class of vulnerability

TridentStack Control continuously scans Linux endpoints for known vulnerabilities and deploys the fixes from the same console. 200 endpoints free forever, no credit card.

Patch your fleet free Start freeThis CVE lookup is free and always will be.

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 2026-06-17.