CVE-2020-15025 [Medium] | Denial of Service in Ntp

ntpd in ntp 4.2.8 before 4.2.8p15 and 4.3.x before 4.3.101 allows remote attackers to cause a denial of service (memory consumption) by sending packets, because memory is not freed in situations where a CMAC key is used and associated with a CMAC algorithm in the ntp.keys file.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-01-19	3.01%	3.12%	+0.10%
2	2025-12-28	1.89%	3.01%	+1.12%
3	2025-12-27	—	1.89%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-01-19

3.01%

3.12%

+0.10%

2025-12-28

1.89%

3.01%

+1.12%

2025-12-27

—

1.89%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
4.4	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.7	3.6	[email protected]
4.9	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.2	3.6	[email protected]
4.0	2.0	MEDIUM	`AV:N/AC:L/Au:S/C:N/I:N/A:P` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:S) A single authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	8.0	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

4.4

3.1

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.7

3.6

[email protected]

4.9

3.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.2

3.6

[email protected]

4.0

2.0

MEDIUM

AV:N/AC:L/Au:S/C:N/I:N/A:P Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:S): A single authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

8.0

2.9

[email protected]

OS Trackers for CVE-2020-15025

vendor	priority	summary	link
`debian`	low	CVE-2020-15025 low priority: Debian including 2 source packages (ntp, ntpsec), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6.	https://security-tracker.debian.org/tracker/CVE-2020-15025
`gentoo`	normal	CVE-2020-15025: 1 GLSA(s) (202007-12), 1 atom(s) (net-misc/ntp); latest impact normal.	https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-15025
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2020-15025
`suse`	medium	CVE-2020-15025 severity moderate: SUSE including 16 source package names (ntp-4.2.8p15-4.10.1, ntp-4.2.8p15-48.30.1, …), 93 product×package rows across 67 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (67 product lines)): Fixed 93.	https://www.suse.com/security/cve/CVE-2020-15025/
`ubuntu`	medium	CVE-2020-15025 medium priority: Ubuntu including 2 source packages (ntp, ntpsec), 32 status rows across 16 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, trusty, upstream, xenial): not-affected 18, DNE 8, ignored 4, needs-triage 1, released 1.	https://ubuntu.com/security/CVE-2020-15025

Affected software / configurations for CVE-2020-15025

Vendor	Product	Version	Raw CPE
ntp	ntp	>= 4.3.97, < 4.3.101	cpe:2.3:a:ntp:ntp::::::::
ntp	ntp	4.2.8	cpe:2.3:a:ntp:ntp:4.2.8:p11::::::
ntp	ntp	4.2.8	cpe:2.3:a:ntp:ntp:4.2.8:p12::::::
ntp	ntp	4.2.8	cpe:2.3:a:ntp:ntp:4.2.8:p13::::::
ntp	ntp	4.2.8	cpe:2.3:a:ntp:ntp:4.2.8:p14::::::
opensuse	leap	15.1	cpe:2.3:o:opensuse:leap:15.1:::::::*
opensuse	leap	15.2	cpe:2.3:o:opensuse:leap:15.2:::::::*
netapp	cloud_backup	—	cpe:2.3:a:netapp:cloud_backup:-:::::::*
netapp	steelstore_cloud_integrated_storage	—	cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:::::::*
netapp	8300_firmware	—	cpe:2.3:o:netapp:8300_firmware:-:::::::*
netapp	8700_firmware	—	cpe:2.3:o:netapp:8700_firmware:-:::::::*
netapp	a400_firmware	—	cpe:2.3:o:netapp:a400_firmware:-:::::::*
netapp	h410c_firmware	—	cpe:2.3:o:netapp:h410c_firmware:-:::::::*
netapp	h300s_firmware	—	cpe:2.3:o:netapp:h300s_firmware:-:::::::*
netapp	h500s_firmware	—	cpe:2.3:o:netapp:h500s_firmware:-:::::::*
netapp	h700s_firmware	—	cpe:2.3:o:netapp:h700s_firmware:-:::::::*
netapp	h300e_firmware	—	cpe:2.3:o:netapp:h300e_firmware:-:::::::*
netapp	h500e_firmware	—	cpe:2.3:o:netapp:h500e_firmware:-:::::::*
netapp	h700e_firmware	—	cpe:2.3:o:netapp:h700e_firmware:-:::::::*
netapp	h410s_firmware	—	cpe:2.3:o:netapp:h410s_firmware:-:::::::*
oracle	zfs_storage_appliance_kit	8.8	cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:::::::*

References for CVE-2020-15025

URL	Tags
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00005.html	Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00044.html	Mailing List Third Party Advisory
https://bugs.gentoo.org/729458	Issue Tracking Third Party Advisory
https://security.gentoo.org/glsa/202007-12	Third Party Advisory
https://security.netapp.com/advisory/ntap-20200702-0002/	Third Party Advisory
https://support.ntp.org/bin/view/Main/NtpBug3661	Vendor Advisory
https://support.ntp.org/bin/view/Main/SecurityNotice#June_2020_ntp_4_2_8p15_NTP_Relea	Release Notes Vendor Advisory
https://www.oracle.com/security-alerts/cpujan2021.html	Patch Third Party Advisory

URL

CVE-2020-15025

Exploit prediction scoring system (EPSS) score for CVE-2020-15025

Common vulnerability scoring system (CVSS) metrics for CVE-2020-15025

Weakness enumeration for CVE-2020-15025

OS Trackers for CVE-2020-15025

Affected software / configurations for CVE-2020-15025

References for CVE-2020-15025