CVE-2018-7183
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote...
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
9.8
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
CVE-2018-7183- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List No score
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
CVE-2018-7183- Updated
- 2026-11-02
EUVDEUVD-2018-18925 No score
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
EUVD-2018-18925- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-9429-whv8-4h3p
9.8
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote...
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
GHSA-9429-whv8-4h3p- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
9.8
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
CVE-2018-7183- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-7183
9.8
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
DEBIAN-CVE-2018-7183- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Show 9 moreShow less
OSVUBUNTU-CVE-2018-7183
9.8
Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.
- Record
UBUNTU-CVE-2018-7183- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVMGASA-2018-0195 No score
Updated ntp packages fix security vulnerabilities
This release addresses five security issues in ntpd for Mageia 6:
LOW/MEDIUM: Sec 3012 / CVE-2016-1549 / VU#961909: Sybil vulnerability: ephemeral association attack While fixed in ntp-4.2.8p7, there are significant additional protections for this issue in 4.2.8p11. Reported by Matt Van Gundy of Cisco.
INFO/MEDIUM: Sec 3412 / CVE-2018-7182 / VU#961909: ctl_getitem(): buffer read overrun leads to undefined behavior and information leak Reported by Yihan Lian of Qihoo 360.
LOW: Sec 3415 / CVE-2018-7170 / VU#961909: Multiple authenticated ephemeral associations. Reported on the questions@ list.
LOW: Sec 3453 / CVE-2018-7184 / VU#961909: Interleaved symmetric mode cannot recover from bad state. Reported by Miroslav Lichvar of Red Hat.
LOW/MEDIUM: Sec 3454 / CVE-2018-7185 / VU#961909: Unauthenticated packet can reset authenticated interleaved association. Reported by Miroslav Lichvar of Red Hat.
one security issue in ntpq: MEDIUM: Sec 3414 / CVE-2018-7183 / VU#961909: ntpq:decodearr() can write beyond its buffer limit. Reported by Michael Macnair of Thales-esecurity.com.
and provides over 33 bugfixes and 32 other improvements. ENotification of these issues were delivered to our Institutional members on a rolling basis as they were reported and as progress was made.
- Record
MGASA-2018-0195- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:11102-1 No score
ntp-4.2.8p15-7.2 on GA media
These are all security issues fixed in the ntp-4.2.8p15-7.2 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:11102-1- Updated
- 2026-11-02
OSVSUSE-SU-2018:0808-1 No score
Security update for ntp
This update for ntp fixes the following issues:
Security issues fixed:
- CVE-2016-1549: Significant additional protections against CVE-2016-1549 that was fixed in ntp-4.2.8p7 (bsc#1082210).
- CVE-2018-7170: Ephemeral association time spoofing additional protection (bsc#1083424).
- CVE-2018-7182: Buffer read overrun leads information leak in ctl_getitem() (bsc#1083426).
- CVE-2018-7183: decodearr() can write beyond its buffer limit (bsc#1083417).
- CVE-2018-7184: Interleaved symmetric mode cannot recover from bad state (bsc#1083422).
- CVE-2018-7185: Unauthenticated packet can reset authenticated interleaved association (bsc#1083420).
Bug fixes:
- bsc#1077445: Don't use libevent's cached time stamps in sntp.
- Disable CMAC in ntp when building against a version of OpenSSL that doesn't support it.
- Record
SUSE-SU-2018:0808-1- Updated
- 2026-11-02
OSVSUSE-SU-2018:0956-1 No score
Security update for ntp
This update for ntp fixes the following issues:
- Update to 4.2.8p11 (bsc#1082210):
- CVE-2016-1549: Sybil vulnerability: ephemeral association attack. While fixed in ntp-4.2.8p7, there are significant additional protections for this issue in 4.2.8p11.
- CVE-2018-7182: ctl_getitem(): buffer read overrun leads to undefined behavior and information leak. (bsc#1083426)
- CVE-2018-7170: Multiple authenticated ephemeral associations. (bsc#1083424)
- CVE-2018-7184: Interleaved symmetric mode cannot recover from bad state. (bsc#1083422)
- CVE-2018-7185: Unauthenticated packet can reset authenticated interleaved association. (bsc#1083420)
- CVE-2018-7183: ntpq:decodearr() can write beyond its buffer limit.(bsc#1083417)
- Don't use libevent's cached time stamps in sntp. (bsc#1077445)
- Record
SUSE-SU-2018:0956-1- Updated
- 2026-11-02
OSVSUSE-SU-2018:1464-1 No score
Security update for ntp
This update for ntp fixes the following issues:
- Update to 4.2.8p11 (bsc#1082210):
- CVE-2016-1549: Sybil vulnerability: ephemeral association attack. While fixed in ntp-4.2.8p7, there are significant additional protections for this issue in 4.2.8p11.
- CVE-2018-7182: ctl_getitem(): buffer read overrun leads to undefined behavior and information leak. (bsc#1083426)
- CVE-2018-7170: Multiple authenticated ephemeral associations. (bsc#1083424)
- CVE-2018-7184: Interleaved symmetric mode cannot recover from bad state. (bsc#1083422)
- CVE-2018-7185: Unauthenticated packet can reset authenticated interleaved association. (bsc#1083420)
- CVE-2018-7183: ntpq:decodearr() can write beyond its buffer limit.(bsc#1083417)
- Don't use libevent's cached time stamps in sntp. (bsc#1077445)
- Fix systemd migration in %pre (bsc#1034892).
- Record
SUSE-SU-2018:1464-1- Updated
- 2026-11-02
OSVSUSE-SU-2018:1765-1 No score
Security update for ntp
This update for ntp fixes the following issues:
- Update to 4.2.8p11 (bsc#1082210):
- CVE-2016-1549: Sybil vulnerability: ephemeral association attack. While fixed in ntp-4.2.8p7, there are significant additional protections for this issue in 4.2.8p11.
- CVE-2018-7182: ctl_getitem(): buffer read overrun leads to undefined behavior and information leak. (bsc#1083426)
- CVE-2018-7170: Multiple authenticated ephemeral associations. (bsc#1083424)
- CVE-2018-7184: Interleaved symmetric mode cannot recover from bad state. (bsc#1083422)
- CVE-2018-7185: Unauthenticated packet can reset authenticated interleaved association. (bsc#1083420)
- CVE-2018-7183: ntpq:decodearr() can write beyond its buffer limit.(bsc#1083417)
- Don't use libevent's cached time stamps in sntp. (bsc#1077445)
This update is a reissue of the previous update with LTSS channels included.
- Record
SUSE-SU-2018:1765-1- Updated
- 2026-11-02
OSVSUSE-SU-2018:1765-2 No score
Security update for ntp
This update for ntp fixes the following issues:
- Update to 4.2.8p11 (bsc#1082210):
- CVE-2016-1549: Sybil vulnerability: ephemeral association attack. While fixed in ntp-4.2.8p7, there are significant additional protections for this issue in 4.2.8p11.
- CVE-2018-7182: ctl_getitem(): buffer read overrun leads to undefined behavior and information leak. (bsc#1083426)
- CVE-2018-7170: Multiple authenticated ephemeral associations. (bsc#1083424)
- CVE-2018-7184: Interleaved symmetric mode cannot recover from bad state. (bsc#1083422)
- CVE-2018-7185: Unauthenticated packet can reset authenticated interleaved association. (bsc#1083420)
- CVE-2018-7183: ntpq:decodearr() can write beyond its buffer limit.(bsc#1083417)
- Don't use libevent's cached time stamps in sntp. (bsc#1077445)
This update is a reissue of the previous update with LTSS channels included.
- Record
SUSE-SU-2018:1765-2- Updated
- 2026-11-02
OSVUSN-3707-1 No score
ntp vulnerabilities
Yihan Lian discovered that NTP incorrectly handled certain malformed mode 6 packets. A remote attacker could possibly use this issue to cause ntpd to crash, resulting in a denial of service. This issue only affected Ubuntu 17.10 and Ubuntu 18.04 LTS. (CVE-2018-7182)
Michael Macnair discovered that NTP incorrectly handled certain responses. A remote attacker could possibly use this issue to execute arbitrary code. (CVE-2018-7183)
Miroslav Lichvar discovered that NTP incorrectly handled certain zero-origin timestamps. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 17.10 and Ubuntu 18.04 LTS. (CVE-2018-7184)
Miroslav Lichvar discovered that NTP incorrectly handled certain zero-origin timestamps. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2018-7185)
- Record
USN-3707-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ntpDebian:11 |
before 1:4.2.8p11+dfsg-1 | 1:4.2.8p11+dfsg-1 |
ntpMageia:6 |
before 4.2.8p11-1.mga6 | 4.2.8p11-1.mga6 |
ntpSUSE:Linux Enterprise Server 11 SP4 |
before 4.2.8p11-64.4.1 | 4.2.8p11-64.4.1 |
ntpSUSE:Linux Enterprise Server for SAP Applications 11 SP4 |
before 4.2.8p11-64.4.1 | 4.2.8p11-64.4.1 |
ntpSUSE:Linux Enterprise Desktop 12 SP3 |
before 4.2.8p11-64.3.2 | 4.2.8p11-64.3.2 |
ntpSUSE:Linux Enterprise Server 12 SP3 |
before 4.2.8p11-64.3.2 | 4.2.8p11-64.3.2 |
ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP3 |
before 4.2.8p11-64.3.2 | 4.2.8p11-64.3.2 |
ntpSUSE:Linux Enterprise Server 12-LTSS |
before 4.2.8p11-46.26.2 | 4.2.8p11-46.26.2 |
ntpSUSE:OpenStack Cloud 7 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Desktop 12 SP3 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
Show 12 moreShow less
| Package | Affected | Fixed |
|---|---|---|
ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP1 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP2 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server 12 SP1-LTSS |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server 12 SP2-LTSS |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server 12 SP3 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP3 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Enterprise Storage 4 |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpSUSE:Linux Enterprise Server 12 SP2-BCL |
before 4.2.8p11-64.5.1 | 4.2.8p11-64.5.1 |
ntpUbuntu:14.04:LTS |
before 1:4.2.6.p5+dfsg-3ubuntu2.14.04.13, plus listed versions 1:4.2.6.p5+dfsg-3ubuntu21:4.2.6.p5+dfsg-3ubuntu2.14.04.11:4.2.6.p5+dfsg-3ubuntu2.14.04.21:4.2.6.p5+dfsg-3ubuntu2.14.04.31:4.2.6.p5+dfsg-3ubuntu2.14.04.5 Show 6 moreShow less1:4.2.6.p5+dfsg-3ubuntu2.14.04.61:4.2.6.p5+dfsg-3ubuntu2.14.04.71:4.2.6.p5+dfsg-3ubuntu2.14.04.81:4.2.6.p5+dfsg-3ubuntu2.14.04.101:4.2.6.p5+dfsg-3ubuntu2.14.04.111:4.2.6.p5+dfsg-3ubuntu2.14.04.12 |
1:4.2.6.p5+dfsg-3ubuntu2.14.04.13 |
ntpUbuntu:16.04:LTS |
before 1:4.2.8p4+dfsg-3ubuntu5.9, plus listed versions 1:4.2.6.p5+dfsg-3ubuntu81:4.2.6.p5+dfsg-3ubuntu8.11:4.2.6.p5+dfsg-3ubuntu91:4.2.8p4+dfsg-3ubuntu11:4.2.8p4+dfsg-3ubuntu2 Show 11 moreShow less1:4.2.8p4+dfsg-3ubuntu31:4.2.8p4+dfsg-3ubuntu41:4.2.8p4+dfsg-3ubuntu51:4.2.8p4+dfsg-3ubuntu5.11:4.2.8p4+dfsg-3ubuntu5.21:4.2.8p4+dfsg-3ubuntu5.31:4.2.8p4+dfsg-3ubuntu5.41:4.2.8p4+dfsg-3ubuntu5.51:4.2.8p4+dfsg-3ubuntu5.61:4.2.8p4+dfsg-3ubuntu5.71:4.2.8p4+dfsg-3ubuntu5.8 |
1:4.2.8p4+dfsg-3ubuntu5.9 |
ntpUbuntu:18.04:LTS |
before 1:4.2.8p10+dfsg-5ubuntu7.1, plus listed versions 1:4.2.8p10+dfsg-5ubuntu31:4.2.8p10+dfsg-5ubuntu41:4.2.8p10+dfsg-5ubuntu51:4.2.8p10+dfsg-5ubuntu61:4.2.8p10+dfsg-5ubuntu7 |
1:4.2.8p10+dfsg-5ubuntu7.1 |
ntpopenSUSE:Tumbleweed |
before 4.2.8p15-7.2 | 4.2.8p15-7.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-7183 is a critical vulnerability (CVSS 9.8) in Ntp, published March 8, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 10.2%, the 95th percentile. Fixed in ntp 1:4.2.8p11+dfsg-1.
References
security.gentoo.org/glsa/201805-12
security.FreeBSD.org/advisories/FreeBSD-SA-18:02.ntp.asc
usn.ubuntu.com/3707-2
usn.ubuntu.com/3707-1
securityfocus.com/bid/103351
oracle.com//security-alerts/cpujul2021.html
Show 51 moreShow less
security.netapp.com/advisory/ntap-20180626-0001
support.ntp.org/bin/view/Main/SecurityNotice
synology.com/support/security/Synology_SA_18_13
support.ntp.org/bin/view/Main/NtpBug3414
support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03962en_us
nvd.nist.gov/vuln/detail/CVE-2018-7183
github.com/advisories/GHSA-9429-whv8-4h3p
security-tracker.debian.org/tracker/CVE-2018-7183
advisories.mageia.org/MGASA-2018-0195.html
bugs.mageia.org/show_bug.cgi?id=22850
suse.com/support/update/announcement/2018/suse-su-20180808-1
bugzilla.suse.com/1077445
bugzilla.suse.com/1082210
bugzilla.suse.com/1083417
bugzilla.suse.com/1083420
bugzilla.suse.com/1083422
bugzilla.suse.com/1083424
bugzilla.suse.com/1083426
suse.com/security/cve/CVE-2016-1549
suse.com/security/cve/CVE-2018-7170
suse.com/security/cve/CVE-2018-7182
suse.com/security/cve/CVE-2018-7183
suse.com/security/cve/CVE-2018-7184
suse.com/security/cve/CVE-2018-7185
suse.com/support/update/announcement/2018/suse-su-20180956-1
bugzilla.suse.com/1082063
suse.com/support/update/announcement/2018/suse-su-20181464-1
bugzilla.suse.com/1034892
suse.com/support/update/announcement/2018/suse-su-20181765-1
suse.com/support/update/announcement/2018/suse-su-20181765-2
ubuntu.com/security/CVE-2018-7183
kb.cert.org/vuls/id/961909
ubuntu.com/security/notices/USN-3707-1
ubuntu.com/security/notices/USN-3707-2
cve.org/CVERecord?id=CVE-2018-7183
ubuntu.com/security/CVE-2018-7182
ubuntu.com/security/CVE-2018-7184
ubuntu.com/security/CVE-2018-7185
suse.com/security/cve/CVE-2016-9042
suse.com/security/cve/CVE-2017-6451
suse.com/security/cve/CVE-2017-6458
suse.com/security/cve/CVE-2017-6460
suse.com/security/cve/CVE-2017-6462
suse.com/security/cve/CVE-2017-6463
suse.com/security/cve/CVE-2017-6464
suse.com/security/cve/CVE-2018-12327
suse.com/security/cve/CVE-2018-8956
suse.com/security/cve/CVE-2019-8936
suse.com/security/cve/CVE-2020-11868
suse.com/security/cve/CVE-2020-13817
suse.com/security/cve/CVE-2020-15025