Description
ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows remote attackers to cause a denial of service (daemon exit or system time change) by predicting transmit timestamps for use in spoofed packets. The victim must be relying on unauthenticated IPv4 time sources. There must be an off-path attacker who can query time from the victim's ntpd instance.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 11 | ntp | 1:4.2.8p14+dfsg-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | ntp | No fix yet | — |
| Ubuntu 16.04 LTS | ntp | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | ntp | No fix yet | — |
| Ubuntu Pro 18.04 LTS | ntp | No fix yet | — |
| Ubuntu Pro 14.04 LTS | ntp | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | ntp +4 | 4.2.6p5-29.el7_8.2 | RHSA-2020:2663 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | ntp | 4.2.8p15-4.10.1 | SUSE-SU-2020:1823-1 |
| SLES 15 SP1 | ntp | 4.2.8p15-4.10.1 | SUSE-SU-2020:1823-1 |
| SLES 15 | ntp | 4.2.8p15-4.10.1 | SUSE-SU-2020:1823-1 |
| SLES 12 SP5 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES 12 SP4 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES 12 SP2 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES 11 SP4 | ntp | 4.2.8p15-64.16.1 | SUSE-SU-2020:14415-1 |
| SLES for SAP 15 | ntp | 4.2.8p15-4.10.1 | SUSE-SU-2020:1823-1 |
| SLES for SAP 12 SP5 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES for SAP 12 SP4 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES for SAP 12 SP3 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SLES for SAP 12 SP2 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SUSE OpenStack Cloud Crowbar 8 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SUSE OpenStack Cloud 8 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SUSE OpenStack Cloud 7 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SUSE HPE Helion OpenStack 8 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
| SUSE Enterprise Storage 5 | ntp | 4.2.8p15-88.1 | SUSE-SU-2020:1805-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | ntp | 4.2.8p15-7.2 | openSUSE-SU-2024:11102-1 |
| openSUSE Leap 15.2 | ntp | 4.2.8p15-lp152.3.3.1 | openSUSE-SU-2020:1007-1 |
| openSUSE Leap 15.1 | ntp | 4.2.8p15-lp151.2.3.1 | openSUSE-SU-2020:0934-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | ntp +4 | 4.2.6p5-29.amzn2.0.2 | ALAS2-2020-1455 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | ntp +4 | 4.2.6p5-29.0.1.el7_8.2 | ELSA-2020-2663 |
Advisories 12
- RHSA-2020:2663 Red Hat Security Advisory: ntp security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- openSUSE-SU-2020:0934-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11102-1 ntp-4.2.8p15-7.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1805-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1823-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1007-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14415-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- ICSA-23-234-01 Hitachi Energy AFF66x CISA ICS & IT advisories · Aug 22, 2023
- WID-SEC-2023-1737 Juniper Patchday Juli 2023 BSI CERT-Bund (WID) · Jul 12, 2023
- VDE-2022-032 AUMA: Multiple Vulnerabilities in Automation Runtime NTP Service CERT@VDE · Aug 9, 2022
- ALAS2-2020-1455 Moderate: ntp security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jul 17, 2020
- ELSA-2020-2663 Moderate: ntp security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jun 24, 2020
References
- openSUSE-SU-2020:0934 vendor-advisory
- openSUSE-SU-2020:1007 vendor-advisory
- GLSA-202007-12 vendor-advisory
- https://www.oracle.com/security-alerts/cpujan2022.html
- http://support.ntp.org/bin/view/Main/NtpBug3596
- https://bugs.ntp.org/show_bug.cgi?id=3596
- https://security.netapp.com/advisory/ntap-20200625-0004/