HIGH
ntp: read_mru_list() does inadequate incoming packet checks
Published Jan 13, 2017
7.5
HIGHCVSS 3.1
EPSS 52.94%
Description
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a crafted mrulist query.
Affected products
No data.
Configuration 1
OR
- ≥ 4.3.0 · < 4.3.94
- 4.2.7
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Configuration 2
- ≥ b.11.31 · < c.4.2.8.2.0
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
| 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 |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue did not affect the versions of ntp as shipped with Red Hat Enterprise Linux 5, 6 and 7 as they did not include support for mrulist.
Metrics
No CVSS v4.0 score for this CVE.
7.5 HIGH NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
5.3 MEDIUM Red Hat
CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
4.3 MEDIUM NVD
AV:N/AC:M/Au:N/C:N/I:N/A:P
Access Vector Network
Access Complexity Medium
Authentication None
Confidentiality Impact None
Integrity Impact None
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
52.94% 0.52935
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.52935
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (47 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 52.94% (0.52935) | 98.94th | v5 (v2026.06.15) |
| Jun 15, 2026 | 52.94% (0.52935) | 98.83th | v5 (v2026.06.15) |
| Mar 4, 2026 | 62.38% (0.62378) | 98.33th | v4 (v2025.03.14) |
| Mar 1, 2026 | 59.01% (0.59011) | 98.20th | v4 (v2025.03.14) |
| Feb 4, 2026 | 62.38% (0.62378) | 98.31th | v4 (v2025.03.14) |
| Feb 1, 2026 | 59.01% (0.59011) | 98.18th | v4 (v2025.03.14) |
| Jan 4, 2026 | 62.38% (0.62378) | 98.29th | v4 (v2025.03.14) |
| Jan 1, 2026 | 59.01% (0.59011) | 98.16th | v4 (v2025.03.14) |
| Dec 28, 2025 | 62.38% (0.62378) | 98.28th | v4 (v2025.03.14) |
| Dec 27, 2025 | 63.46% (0.63460) | 98.34th | v4 (v2025.03.14) |
| Dec 15, 2025 | 62.38% (0.62378) | 98.27th | v4 (v2025.03.14) |
| Dec 13, 2025 | 64.52% (0.64521) | 98.37th | v4 (v2025.03.14) |
| Dec 4, 2025 | 63.46% (0.63460) | 98.31th | v4 (v2025.03.14) |
| Dec 1, 2025 | 60.16% (0.60156) | 98.19th | v4 (v2025.03.14) |
| Nov 4, 2025 | 63.46% (0.63460) | 98.31th | v4 (v2025.03.14) |
| Nov 1, 2025 | 60.16% (0.60156) | 98.18th | v4 (v2025.03.14) |
| Oct 4, 2025 | 63.46% (0.63460) | 98.34th | v4 (v2025.03.14) |
| Oct 1, 2025 | 60.16% (0.60156) | 98.23th | v4 (v2025.03.14) |
| Sep 16, 2025 | 63.46% (0.63460) | 98.36th | v4 (v2025.03.14) |
| Sep 4, 2025 | 68.68% (0.68679) | 98.57th | v4 (v2025.03.14) |
| Sep 1, 2025 | 65.73% (0.65734) | 98.46th | v4 (v2025.03.14) |
| Aug 19, 2025 | 68.68% (0.68679) | 98.55th | v4 (v2025.03.14) |
| Aug 4, 2025 | 71.73% (0.71728) | 98.66th | v4 (v2025.03.14) |
| Aug 1, 2025 | 61.20% (0.61204) | 98.25th | v4 (v2025.03.14) |
| Jul 5, 2025 | 71.73% (0.71728) | 98.65th | v4 (v2025.03.14) |
| Jul 1, 2025 | 61.20% (0.61204) | 98.22th | v4 (v2025.03.14) |
| Jun 5, 2025 | 71.73% (0.71728) | 98.63th | v4 (v2025.03.14) |
| Jun 1, 2025 | 61.20% (0.61204) | 98.20th | v4 (v2025.03.14) |
| May 20, 2025 | 71.73% (0.71728) | 98.63th | v4 (v2025.03.14) |
| May 18, 2025 | 61.20% (0.61204) | 98.19th | v4 (v2025.03.14) |
| May 4, 2025 | 71.73% (0.71728) | 98.63th | v4 (v2025.03.14) |
| May 1, 2025 | 61.20% (0.61204) | 98.19th | v4 (v2025.03.14) |
| Apr 2, 2025 | 71.73% (0.71728) | 98.65th | v4 (v2025.03.14) |
| Apr 1, 2025 | 61.20% (0.61204) | 98.16th | v4 (v2025.03.14) |
| Mar 30, 2025 | 71.73% (0.71728) | 98.65th | v4 (v2025.03.14) |
| Mar 29, 2025 | 74.34% (0.74345) | 98.49th | v4 (v2025.03.14) |
| Mar 28, 2025 | 71.73% (0.71728) | 98.64th | v4 (v2025.03.14) |
| Mar 27, 2025 | 74.34% (0.74345) | 98.73th | v4 (v2025.03.14) |
| Mar 20, 2025 | 71.73% (0.71728) | 98.68th | v4 (v2025.03.14) |
| Mar 19, 2025 | 74.34% (0.74345) | 98.76th | v4 (v2025.03.14) |
| Mar 18, 2025 | 71.73% (0.71728) | 98.67th | v4 (v2025.03.14) |
| Mar 17, 2025 | 61.20% (0.61204) | 98.13th | v4 (v2025.03.14) |
| Dec 12, 2024 | 96.18% (0.96178) | 99.58th | v3 (v2023.03.01) |
| Apr 19, 2023 | 96.45% (0.96455) | 99.28th | v3 (v2023.03.01) |
| Mar 7, 2023 | 96.55% (0.96550) | 99.28th | v3 (v2023.03.01) |
| Mar 6, 2023 | 43.88% (0.43883) | 98.34th | v2 (v2022.01.01) |
| Feb 4, 2022 | 43.88% (0.43883) | 97.69th | v2 (v2022.01.01) |
Weaknesses (1)
References (15)
- http://nwtime.org/ntp428p9_release/ x_refsource_CONFIRMThird Party Advisory
- http://support.ntp.org/bin/view/Main/NtpBug3082 x_refsource_CONFIRMIssue TrackingMitigationVendor Advisory
- http://support.ntp.org/bin/view/Main/NtpBug3102
- http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities x_refsource_CONFIRMRelease NotesVendor Advisory
- http://www.securityfocus.com/bid/94448 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1037354 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2016-7434 Vendor Advisory
- https://bto.bluecoat.com/security-advisory/sa139 x_refsource_CONFIRMThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1397334 Issue Tracking
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03706en_us x_refsource_CONFIRMThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2016-7434
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:39.ntp.asc vendor-advisoryx_refsource_FREEBSDThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2016-7434
- https://www.exploit-db.com/exploits/40806/ exploitx_refsource_EXPLOIT-DBThird Party AdvisoryVDB Entry
- https://www.kb.cert.org/vuls/id/633847 third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Jan 13, 2017
Updated Aug 6, 2024
Reserved Sep 9, 2016
Link CVE-2016-7434
CISA Vulnrichment
Updated n/a