MEDIUM
ntp: restriction list NULL pointer dereference
Published Jan 30, 2017
5.9
MEDIUMCVSS 3.1
EPSS 6.35%
Description
ntpd in NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (NULL pointer dereference) via a ntpdc reslist command.
Affected products
No data.
Configuration 1
OR
- ≤ 4.2.8
- ≥ 4.3.0 · < 4.3.90
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
- 4.2.8
Configuration 3
AND
- n/a
Configuration 4
AND
- n/a
Running on/with
- n/a
Configuration 5
OR
- n/a
- n/a
Configuration 6
OR
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 9.3
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.1
- 10.2
- 10.2
- 10.2
- 10.2
- 10.2
- 10.2
- 10.2
- 10.2
Configuration 7
OR
- 22
- 23
Configuration 8
OR
- 8.0
- 9.0
Configuration 9
OR
- 12.04
- 14.04
- 16.04
No data.
Red Hat Enterprise Linux 6
ntp-0:4.2.6p5-10.el6
Fixed · RHSA-2016:0780
Red Hat Enterprise Linux 7
ntp-0:4.2.6p5-25.el7
Fixed · RHSA-2016:2583
Red Hat Enterprise Linux 5
ntp
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | ntp-0:4.2.6p5-10.el6 | Fixed | RHSA-2016:0780 |
| Red Hat Enterprise Linux 7 | ntp-0:4.2.6p5-25.el7 | Fixed | RHSA-2016:2583 |
| Red Hat Enterprise Linux 5 | ntp | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the versions of ntp as shipped with Red Hat Enterprise Linux 5, 6, and 7. Red Hat Product Security has rated this issue as having Moderate security impact. A future update may address this issue in Red Hat Enterprise Linux 6 and 7. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
Red Hat mitigation
Keep the number of restriction list entries in ntp.conf lower than 500.
Metrics
No CVSS v4.0 score for this CVE.
5.9 MEDIUM NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
No CVSS v3.0 score for this CVE.
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.
6.35% 0.06346
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.06346
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 (21 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.35% (0.06346) | 93.43th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.35% (0.06346) | 92.72th | v5 (v2026.06.15) |
| Mar 13, 2026 | 16.35% (0.16351) | 94.75th | v4 (v2025.03.14) |
| Feb 18, 2026 | 14.84% (0.14842) | 94.36th | v4 (v2025.03.14) |
| Jan 14, 2026 | 18.91% (0.18911) | 95.10th | v4 (v2025.03.14) |
| Aug 10, 2025 | 9.71% (0.09711) | 92.59th | v4 (v2025.03.14) |
| Jul 7, 2025 | 11.63% (0.11631) | 93.32th | v4 (v2025.03.14) |
| Mar 30, 2025 | 7.04% (0.07043) | 90.61th | v4 (v2025.03.14) |
| Mar 29, 2025 | 13.79% (0.13791) | 90.47th | v4 (v2025.03.14) |
| Mar 17, 2025 | 7.04% (0.07043) | 90.82th | v4 (v2025.03.14) |
| Dec 17, 2024 | 6.56% (0.06557) | 93.68th | v3 (v2023.03.01) |
| Dec 12, 2024 | 1.87% (0.01870) | 88.89th | v3 (v2023.03.01) |
| May 2, 2024 | 1.63% (0.01634) | 87.38th | v3 (v2023.03.01) |
| Feb 12, 2024 | 1.35% (0.01347) | 85.70th | v3 (v2023.03.01) |
| Jan 3, 2024 | 1.15% (0.01147) | 83.20th | v3 (v2023.03.01) |
| Nov 21, 2023 | 1.11% (0.01111) | 82.89th | v3 (v2023.03.01) |
| May 6, 2023 | 0.75% (0.00750) | 78.31th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.74% (0.00739) | 77.88th | v3 (v2023.03.01) |
| Mar 6, 2023 | 4.36% (0.04358) | 88.02th | v2 (v2022.01.01) |
| Apr 1, 2022 | 4.36% (0.04358) | 86.83th | v2 (v2022.01.01) |
| Feb 4, 2022 | 4.36% (0.04358) | 70.59th | v2 (v2022.01.01) |
Weaknesses (1)
References (33)
- http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177507.html vendor-advisoryx_refsource_FEDORAThird Party Advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2016-January/176434.html vendor-advisoryx_refsource_FEDORAThird Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00059.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00060.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00020.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00038.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00048.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html vendor-advisoryx_refsource_SUSEThird Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html vendor-advisoryx_refsource_SUSEBroken Link
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00114.html vendor-advisoryx_refsource_SUSEBroken Link
- http://rhn.redhat.com/errata/RHSA-2016-0780.html vendor-advisoryx_refsource_REDHATBroken Link
- http://rhn.redhat.com/errata/RHSA-2016-2583.html vendor-advisoryx_refsource_REDHATBroken Link
- http://support.ntp.org/bin/view/Main/NtpBug2939 x_refsource_CONFIRMVendor Advisory
- http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_Security x_refsource_CONFIRMVendor Advisory
- http://support.ntp.org/bin/view/Main/SecurityNotice#January_2016_NTP_4_2_8p6_Securit
- http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160127-ntpd vendor-advisoryx_refsource_CISCOThird Party Advisory
- http://www.debian.org/security/2016/dsa-3629 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html x_refsource_CONFIRMThird Party Advisory
- http://www.securityfocus.com/bid/81815 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1034782 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- http://www.talosintel.com/reports/TALOS-2016-0074/
- http://www.ubuntu.com/usn/USN-3096-1 vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2015-7977 Vendor Advisory
- https://bto.bluecoat.com/security-advisory/sa113 x_refsource_CONFIRMThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1300269 Issue Tracking
- https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf x_refsource_CONFIRMThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-7977
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:09.ntp.asc vendor-advisoryx_refsource_FREEBSDThird Party Advisory
- https://security.gentoo.org/glsa/201607-15 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://security.netapp.com/advisory/ntap-20171031-0001/ x_refsource_CONFIRMThird Party Advisory
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11 x_refsource_CONFIRMThird Party AdvisoryUS Government Resource
- https://www.cve.org/CVERecord?id=CVE-2015-7977
- https://www.kb.cert.org/vuls/id/718152 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 30, 2017
Updated Aug 6, 2024
Reserved Oct 23, 2015
Link CVE-2015-7977
CISA Vulnrichment
Updated n/a