How severe is CVE-2020-11868?

CVE-2020-11868 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-11868 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11868?

CVE-2020-11868 primarily affects Ntp. In total, 46 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-11868?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-11868 published?

CVE-2020-11868 was published on 2020-04-17 and last updated on 2026-06-17.

CVE-2020-11868

CVE-2020-11868 is a high-severity vulnerability in Ntp with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-346.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-346
Affected product: Ntp
Published: 2020-04-17
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2020-11868?: 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 severe is CVE-2020-11868?: CVE-2020-11868 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-11868 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11868?: CVE-2020-11868 primarily affects Ntp. In total, 46 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-11868?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-11868 published?: CVE-2020-11868 was published on 2020-04-17 and last updated on 2026-06-17.

References

Affected products (46)

cpe:2.3:a:ntp:ntp:*:*:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:-:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-beta1:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-beta2:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-beta3:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-beta4:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-beta5:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-rc1:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p1-rc2:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p10:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p11:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p12:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p13:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p2:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p2-rc1:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p2-rc2:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p2-rc3:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p3:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p3-rc1:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p3-rc2:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p3-rc3:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p4:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p5:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p6:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p7:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p8:*:*:*:*:*:*
cpe:2.3:a:ntp:ntp:4.2.8:p9:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:a:netapp:data_ontap:-:*:*:*:*:7-mode:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:vasa_provider_for_clustered_data_ontap:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:vasa_provider_for_clustered_data_ontap:*:*:*:*:*:vsphere:*:*
cpe:2.3:a:netapp:virtual_storage_console:*:*:*:*:*:vsphere:*:*
cpe:2.3:o:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:hci_storage_node_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:fabric-attached_storage_8300_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:fabric-attached_storage_8700_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:fabric-attached_storage_a400_firmware:-:*:*:*:*:*:*:*

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CVE-2015-7871 — Critical (CVSS 9.8): Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass…
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All CVEs affecting Ntp →

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Browse all CWE-346 vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

197.248.207.139 (ipv4-addr)
223.197.153.135 (ipv4-addr)
135.129.128.247 (ipv4-addr)
119.201.59.224 (ipv4-addr)
42.200.60.186 (ipv4-addr)
125.212.244.35 (ipv4-addr)
186.182.105.49 (ipv4-addr)
202.29.220.126 (ipv4-addr)