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Public proof of conceptFix available

CVE-2018-12327

A public proof of concept exists; no exploitation attested.

  • Published2018-06-20
  • WeaknessCWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Stack-based buffer overflow in ntpq and ntpdc of NTP version 4.2.8p11 allows an attacker to achieve code execution or escalate to higher privileges via a long string as the argument for an IPv4 or IPv6 command-line parameter. NOTE: It is unclear whether there are any common situations in which ntpq or ntpdc is used with a command line from an untrusted source.

Timeline

dates in UTC
  1. 2018-06-20Exploit-DB entryExploit-DB

Observed activity

isMalicious corpus · updated 2026-11-04 03:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2018-12327?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2018-12327?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Ntp
BranchAffectedFixed in
4.2= 4.2.8no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • ntpUbuntu:Pro:18.04:LTSall versions · fixed in 1:4.2.8p10+dfsg-5ubuntu7.3+esm1
  • ntpUbuntu:Pro:14.04:LTSall versions · fixed in 1:4.2.6.p5+dfsg-3ubuntu2.14.04.13+esm1
  • ntpUbuntu:16.04:LTSall versions · fixed in 1:4.2.8p4+dfsg-3ubuntu5.10
  • ntpTuxCare:Ubuntu:18.04all versions · fixed in 1:4.2.8p10+dfsg-5ubuntu7.3+tuxcare.els1and 3 other packages
  • ntpSUSE:OpenStack Cloud 7all versions · fixed in 4.2.8p12-64.8.2
  • ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP3all versions · fixed in 4.2.8p12-64.8.2
  • ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP2all versions · fixed in 4.2.8p12-64.8.2
  • ntpSUSE:Linux Enterprise Server for SAP Applications 12 SP1all versions · fixed in 4.2.8p12-64.8.2

28 more package ranges on OSV.dev

Vendor advisories

  • CVE-2018-12327 Red Hat Product Security482 products fixed · 1 known affected

    ntp: Stack-based buffer overflow in ntpq and ntpdc allows denial of service or code execution

    ntp as a component of Red Hat Enterprise Linux 5

  • RHSA-2020:1470 Red Hat Product Security44 products fixed

    Red Hat Security Advisory: ntp security update

  • RHSA-2019:2077 Red Hat Product Security47 products fixed

    Red Hat Security Advisory: ntp security, bug fix, and enhancement update

  • RHSA-2018:3854 Red Hat Product Security53 products fixed

    Red Hat Security Advisory: ntp security update

  • RHSA-2018:3853 Red Hat Product Security29 products fixed

    Red Hat Security Advisory: ntp security update

Full record on NVD

Fix

  1. Vendor fix Red Hat Product Security RHSA-2020:1470 · 44 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the ntpd daemon will restart automatically.
  2. No fix planned, says the vendor Red Hat Product Security CVE-2018-12327 · 1 productWill not fix

Detection

read 2026-11-03 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
EDB-44909
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.09.8read 2026-10-23
  • NVDCVSS 2.07.5read 2026-10-23
  • NVDweakness (CWE)CWE-787read 2026-10-23
  • FIRST EPSSEPSS score27.5 %read 2026-11-03
  • Exploit-DBdetectionread 2026-11-03
  • OSVaffected packages—

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2018-06-20
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2018-12327?

Stack-based buffer overflow in ntpq and ntpdc of NTP version 4.2.8p11 allows an attacker to achieve code execution or escalate to higher privileges via a long string as the argument for an IPv4 or IPv6 command-line parameter. NOTE: It is unclear whether there are any common situations in which ntpq or ntpdc is used with a command line from an untrusted source.

Is CVE-2018-12327 actively exploited?

Active exploitation of CVE-2018-12327 has not been confirmed. Its EPSS score was 27.5% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2018-12327?

CVE-2018-12327 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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