Description
ntpd in ntp 4.2.8 before 4.2.8p15 and 4.3.x before 4.3.101 allows remote attackers to cause a denial of service (memory consumption) by sending packets, because memory is not freed in situations where a CMAC key is used and associated with a CMAC algorithm in the ntp.keys file.
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 | 1:4.2.8p15-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | ntp | 1:4.2.8p12+dfsg-3ubuntu4.20.04.1+esm1 | USN-5175-1 |
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 |
Advisories 8
- USN-5175-1 ntp vulnerability Ubuntu Security Notices (USN) · Feb 10, 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
- VDE-2022-032 AUMA: Multiple Vulnerabilities in Automation Runtime NTP Service CERT@VDE · Aug 9, 2022
References
- https://support.ntp.org/bin/view/Main/SecurityNotice#June_2020_ntp_4_2_8p15_NTP_Relea
- https://support.ntp.org/bin/view/Main/NtpBug3661
- https://bugs.gentoo.org/729458
- openSUSE-SU-2020:0934 vendor-advisory
- openSUSE-SU-2020:1007 vendor-advisory
- GLSA-202007-12 vendor-advisory
- https://www.oracle.com/security-alerts/cpujan2021.html
- https://security.netapp.com/advisory/ntap-20200702-0002/