ntp: Interleaved symmetric mode cannot recover from bad state
Published Mar 6, 2018
7.5
HIGHCVSS 3.0
EPSS 8.53%
Description
ntpd in ntp 4.2.8p4 before 4.2.8p11 drops bad packets before updating the "received" timestamp, which allows remote attackers to cause a denial of service (disruption) by sending a packet with a zero-origin timestamp causing the association to reset and setting the contents of the packet as the most recent timestamp. This issue is a result of an incomplete fix for CVE-2015-7704.
Affected products
No data.
Configuration 1
Configuration 2
- 1.1
- n/a
- n/a
- 5.2
- 6.0
- 6.1
Configuration 3
- n/a
Configuration 4
- 14.0
- 14.1
- 14.2
Configuration 5
- 14.04
- 16.04
- 17.10
- 18.04
Configuration 6
- n/a
- n/a
No data.
Red Hat Enterprise Linux 5
ntp
Not affected
Red Hat Enterprise Linux 6
ntp
Not affected
Red Hat Enterprise Linux 7
ntp
Not affected
Red Hat Enterprise Linux 8
ntp
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | ntp | Not affected | n/a |
| Red Hat Enterprise Linux 6 | ntp | Not affected | n/a |
| Red Hat Enterprise Linux 7 | ntp | Not affected | n/a |
| Red Hat Enterprise Linux 8 | ntp | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (27 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 8.53% (0.08527) | 94.89th | v5 (v2026.06.15) |
| Jun 15, 2026 | 8.86% (0.08862) | 94.52th | v5 (v2026.06.15) |
| Dec 28, 2025 | 13.06% (0.13062) | 93.86th | v4 (v2025.03.14) |
| Dec 27, 2025 | 6.42% (0.06420) | 90.77th | v4 (v2025.03.14) |
| Dec 20, 2025 | 13.06% (0.13062) | 93.86th | v4 (v2025.03.14) |
| Dec 15, 2025 | 11.40% (0.11402) | 93.31th | v4 (v2025.03.14) |
| Dec 14, 2025 | 12.61% (0.12608) | 93.70th | v4 (v2025.03.14) |
| Dec 13, 2025 | 10.61% (0.10607) | 93.02th | v4 (v2025.03.14) |
| Nov 21, 2025 | 6.42% (0.06420) | 90.64th | v4 (v2025.03.14) |
| Nov 18, 2025 | 7.45% (0.07449) | 90.85th | v4 (v2025.03.14) |
| Aug 10, 2025 | 6.02% (0.06022) | 90.34th | v4 (v2025.03.14) |
| Apr 30, 2025 | 4.13% (0.04127) | 87.96th | v4 (v2025.03.14) |
| Mar 17, 2025 | 6.42% (0.06420) | 90.35th | v4 (v2025.03.14) |
| Feb 6, 2025 | 10.55% (0.10553) | 95.07th | v3 (v2023.03.01) |
| Dec 17, 2024 | 9.03% (0.09034) | 94.61th | v3 (v2023.03.01) |
| Jun 9, 2024 | 2.86% (0.02857) | 90.74th | v3 (v2023.03.01) |
| May 1, 2024 | 3.99% (0.03993) | 91.94th | v3 (v2023.03.01) |
| Jul 28, 2023 | 3.57% (0.03570) | 90.36th | v3 (v2023.03.01) |
| Jul 8, 2023 | 4.19% (0.04186) | 91.00th | v3 (v2023.03.01) |
| Mar 7, 2023 | 4.17% (0.04168) | 90.87th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.17% (0.02172) | 80.77th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.17% (0.02172) | 78.91th | v2 (v2022.01.01) |
| Feb 4, 2022 | 2.17% (0.02172) | 57.73th | v2 (v2022.01.01) |
| Feb 3, 2022 | 3.52% (0.03521) | 68.37th | v1 |
| Jan 6, 2022 | 3.52% (0.03521) | 68.07th | v1 |
| Sep 1, 2021 | 3.52% (0.03521) | 82.02th | v1 |
| Apr 14, 2021 | 3.52% (0.03521) | 0.00th | v1 |
No CWE recorded.
References (14)
- http://packetstormsecurity.com/files/146631/Slackware-Security-Advisory-ntp-Updates.html x_refsource_MISCThird Party AdvisoryVDB Entry
- http://support.ntp.org/bin/view/Main/NtpBug3453 x_refsource_CONFIRMThird Party Advisory
- http://www.securityfocus.com/archive/1/541824/100/0/threaded mailing-listx_refsource_BUGTRAQThird Party AdvisoryVDB Entry
- http://www.securityfocus.com/bid/103192 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2018-7184 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1550218 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2018-7184
- https://security.FreeBSD.org/advisories/FreeBSD-SA-18:02.ntp.asc vendor-advisoryx_refsource_FREEBSDThird Party Advisory
- https://security.gentoo.org/glsa/201805-12 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://security.netapp.com/advisory/ntap-20180626-0001/ x_refsource_CONFIRMThird Party Advisory
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03962en_us x_refsource_CONFIRM
- https://usn.ubuntu.com/3707-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2018-7184
- https://www.synology.com/support/security/Synology_SA_18_13 x_refsource_CONFIRMThird Party Advisory
Change history (0)
No recorded changes yet.