Description
The getresponse function in ntpq in NTP versions before 4.2.8p9 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (infinite loop) via crafted packets with incorrect values.
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 | 1:4.2.8p7+dfsg-1 | — |
| Debian 8 | ntp | 1:4.2.6.p5+dfsg-7+deb8u2 | DSA-3629-1 |
| Debian 7 | ntp | 1:4.2.6.p5+dfsg-2+deb7u7 | DLA-559-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | ntp | 1:4.2.8p4+dfsg-3ubuntu5.3 | USN-3096-1 |
| Ubuntu 14.04 LTS | ntp | 1:4.2.6.p5+dfsg-3ubuntu2.14.04.10 | USN-3096-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | ntp +4 | 4.2.6p5-25.el7 | RHSA-2016:2583 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP1 | ntp | 4.2.8p6-8.2 | SUSE-SU-2016:1177-1 |
| SLES 12 SP1 | yast2-ntp-client | 3.1.22-6.2 | SUSE-SU-2016:1177-1 |
| SLES 12 | ntp | 4.2.8p6-46.5.2 | SUSE-SU-2016:1247-1 |
| SLES 12 | yast2-ntp-client | 3.1.12.4-8.2 | SUSE-SU-2016:1247-1 |
| SLES 11 SP4 | ntp | 4.2.8p6-8.2 | SUSE-SU-2016:1175-1 |
| SLES 11 SP3 | ntp | 4.2.8p6-41.1 | SUSE-SU-2016:1311-1 |
| SLES 11 SP2 | ntp | 4.2.8p6-41.1 | SUSE-SU-2016:1311-1 |
| SLES 11 SP2 | yast2-ntp-client | 2.17.14.1-1.12.1 | SUSE-SU-2016:1311-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP1 | ntp | 4.2.8p6-8.2 | SUSE-SU-2016:1177-1 |
| SLES for SAP 12 SP1 | yast2-ntp-client | 3.1.22-6.2 | SUSE-SU-2016:1177-1 |
| SLES for SAP 12 | ntp | 4.2.8p6-46.5.2 | SUSE-SU-2016:1247-1 |
| SLES for SAP 12 | yast2-ntp-client | 3.1.12.4-8.2 | SUSE-SU-2016:1247-1 |
| SLES for SAP 11 SP4 | ntp | 4.2.8p6-8.2 | SUSE-SU-2016:1175-1 |
| SUSE OpenStack Cloud 5 | ntp | 4.2.8p6-41.1 | SUSE-SU-2016:1311-1 |
| SUSE Manager Proxy 2.1 | ntp | 4.2.8p6-41.1 | SUSE-SU-2016:1311-1 |
| SUSE Manager 2.1 | ntp | 4.2.8p6-41.1 | SUSE-SU-2016:1311-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | ntp | 4.2.8p9-1.1 | openSUSE-SU-2024:10181-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | ntp +4 | 4.2.6p5-25.0.1.el7 | ELSA-2016-2583 |
Advisories 11
- RHSA-2016:2583 Red Hat Security Advisory: ntp security and bug fix update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DLA-559-1 ntp - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3629-1 ntp - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-3096-1 ntp vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2016:1311-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:1177-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:1247-1 Security update for ntp SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10181-1 ntp-4.2.8p9-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:1175-1 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
- ELSA-2016-2583 Moderate: ntp security and bug fix update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 9, 2016
References
- DSA-3629 vendor-advisory
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03766en_us
- 1034782 vdb-entry
- VU#718152 third-party-advisory
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03750en_us
- RHSA-2016:2583 vendor-advisory
- 81814 vdb-entry
- https://security.netapp.com/advisory/ntap-20171031-0001/
- http://support.ntp.org/bin/view/Main/NtpBug2948
- FreeBSD-SA-16:09 vendor-advisory
- GLSA-201607-15 vendor-advisory