Ntp Ntp

Don't miss out!

Thousands of developers use stack.watch to stay informed.
Get an email whenever new security vulnerabilities are reported in Ntp.

By the Year

In 2025 there have been 0 vulnerabilities in Ntp. Ntp did not have any published security vulnerabilities last year.




Year Vulnerabilities Average Score
2025 0 0.00
2024 0 0.00
2023 5 5.76
2022 0 0.00
2021 0 0.00
2020 5 6.32
2019 2 7.80
2018 7 7.61

It may take a day or so for new Ntp vulnerabilities to show up in the stats or in the list of recent security vulnerabilties. Additionally vulnerabilities may be tagged under a different product or component name.

Recent Ntp Security Vulnerabilities

praecis_parse in ntpd/refclock_palisade.c in NTP 4.2.8p15 has an out-of-bounds write

CVE-2023-26555 6.4 - Medium - April 11, 2023

praecis_parse in ntpd/refclock_palisade.c in NTP 4.2.8p15 has an out-of-bounds write. Any attack method would be complex, e.g., with a manipulated GPS receiver.

Memory Corruption

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when adding a '\0' character

CVE-2023-26554 5.6 - Medium - April 11, 2023

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when adding a '\0' character. An adversary may be able to attack a client ntpq process, but cannot attack ntpd.

Memory Corruption

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when copying the trailing number

CVE-2023-26553 5.6 - Medium - April 11, 2023

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when copying the trailing number. An adversary may be able to attack a client ntpq process, but cannot attack ntpd.

Memory Corruption

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when adding a decimal point

CVE-2023-26552 5.6 - Medium - April 11, 2023

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write when adding a decimal point. An adversary may be able to attack a client ntpq process, but cannot attack ntpd.

Memory Corruption

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write in the cp<cpdec while loop

CVE-2023-26551 5.6 - Medium - April 11, 2023

mstolfp in libntp/mstolfp.c in NTP 4.2.8p15 has an out-of-bounds write in the cp<cpdec while loop. An adversary may be able to attack a client ntpq process, but cannot attack ntpd.

Memory Corruption

ntpd in ntp 4.2.8 before 4.2.8p15 and 4.3.x before 4.3.101

CVE-2020-15025 4.9 - Medium - June 24, 2020

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.

Memory Leak

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100

CVE-2020-13817 7.4 - High - June 04, 2020

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows remote attackers to cause a denial of service (daemon exit or system time change) by predicting transmit timestamps for use in spoofed packets. The victim must be relying on unauthenticated IPv4 time sources. There must be an off-path attacker who can query time from the victim's ntpd instance.

Use of Insufficiently Random Values

ntpd in ntp 4.2.8p10, 4.2.8p11, 4.2.8p12 and 4.2.8p13

CVE-2018-8956 5.3 - Medium - May 06, 2020

ntpd in ntp 4.2.8p10, 4.2.8p11, 4.2.8p12 and 4.2.8p13 allow remote attackers to prevent a broadcast client from synchronizing its clock with a broadcast NTP server via soofed mode 3 and mode 5 packets. The attacker must either be a part of the same broadcast network or control a slave in that broadcast network that can capture certain required packets on the attacker's behalf and send them to the attacker.

Improper Input Validation

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100

CVE-2020-11868 7.5 - High - April 17, 2020

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address, because transmissions are rescheduled even when a packet lacks a valid origin timestamp.

Origin Validation Error

Directory traversal vulnerability in the save_config function in ntpd in ntp_control.c in NTP before 4.2.8p4, when used on systems

CVE-2015-7851 6.5 - Medium - January 28, 2020

Directory traversal vulnerability in the save_config function in ntpd in ntp_control.c in NTP before 4.2.8p4, when used on systems that do not use '\' or '/' characters for directory separation such as OpenVMS, allows remote authenticated users to overwrite arbitrary files.

Directory traversal

NTP through 4.2.8p12 has a NULL Pointer Dereference.

CVE-2019-8936 7.5 - High - May 15, 2019

NTP through 4.2.8p12 has a NULL Pointer Dereference.

NULL Pointer Dereference

Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required

CVE-2019-11331 8.1 - High - April 18, 2019

Network Time Protocol (NTP), as specified in RFC 5905, uses port 123 even for modes where a fixed port number is not required, which makes it easier for remote attackers to conduct off-path attacks.

Stack-based buffer overflow in ntpq and ntpdc of NTP version 4.2.8p11

CVE-2018-12327 9.8 - Critical - June 20, 2018

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.

Memory Corruption

An exploitable denial of service vulnerability exists in the origin timestamp check functionality of ntpd 4.2.8p9

CVE-2016-9042 5.9 - Medium - June 04, 2018

An exploitable denial of service vulnerability exists in the origin timestamp check functionality of ntpd 4.2.8p9. A specially crafted unauthenticated network packet can be used to reset the expected origin timestamp for target peers. Legitimate replies from targeted peers will fail the origin timestamp check (TEST2) causing the reply to be dropped and creating a denial of service condition.

Improper Input Validation

Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10

CVE-2018-7183 9.8 - Critical - March 08, 2018

Buffer overflow in the decodearr function in ntpq in ntp 4.2.8p6 through 4.2.8p10 allows remote attackers to execute arbitrary code by leveraging an ntpq query and sending a response with a crafted array.

Memory Corruption

The protocol engine in ntp 4.2.6 before 4.2.8p11

CVE-2018-7185 7.5 - High - March 06, 2018

The protocol engine in ntp 4.2.6 before 4.2.8p11 allows a remote attackers to cause a denial of service (disruption) by continually sending a packet with a zero-origin timestamp and source IP address of the "other side" of an interleaved association causing the victim ntpd to reset its association.

ntpd in ntp 4.2.8p4 before 4.2.8p11 drops bad packets before updating the "received" timestamp, which

CVE-2018-7184 7.5 - High - March 06, 2018

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.

The ctl_getitem method in ntpd in ntp-4.2.8p6 before 4.2.8p11

CVE-2018-7182 7.5 - High - March 06, 2018

The ctl_getitem method in ntpd in ntp-4.2.8p6 before 4.2.8p11 allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted mode 6 packet with a ntpd instance from 4.2.8p6 through 4.2.8p10.

Out-of-bounds Read

ntpd in ntp 4.2.x before 4.2.8p7 and 4.3.x before 4.3.92 allows authenticated users

CVE-2018-7170 5.3 - Medium - March 06, 2018

ntpd in ntp 4.2.x before 4.2.8p7 and 4.3.x before 4.3.92 allows authenticated users that know the private symmetric key to create arbitrarily-many ephemeral associations in order to win the clock selection of ntpd and modify a victim's clock via a Sybil attack. This issue exists because of an incomplete fix for CVE-2016-1549.

ntp-keygen in ntp 4.2.8px before 4.2.8p2-RC2 and 4.3.x before 4.3.12 does not generate MD5 keys with sufficient entropy on big endian machines when the lowest order byte of the temp variable is between 0x20 and 0x7f and not #, which might

CVE-2015-3405 7.5 - High - August 09, 2017

ntp-keygen in ntp 4.2.8px before 4.2.8p2-RC2 and 4.3.x before 4.3.12 does not generate MD5 keys with sufficient entropy on big endian machines when the lowest order byte of the temp variable is between 0x20 and 0x7f and not #, which might allow remote attackers to obtain the value of generated MD5 keys via a brute force attack with the 93 possible keys.

Insufficient Entropy

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7702 6.5 - Medium - August 07, 2017

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (crash). NOTE: This vulnerability exists due to an incomplete fix for CVE-2014-9750.

Improper Input Validation

Buffer overflow in the password management functionality in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7854 8.8 - High - August 07, 2017

Buffer overflow in the password management functionality in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote authenticated users to cause a denial of service (daemon crash) or possibly execute arbitrary code via a crafted key file.

Classic Buffer Overflow

Memory leak in the CRYPTO_ASSOC function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7701 7.5 - High - August 07, 2017

Memory leak in the CRYPTO_ASSOC function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (memory consumption).

Missing Release of Resource after Effective Lifetime

The ntpd client in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77

CVE-2015-7704 7.5 - High - August 07, 2017

The ntpd client in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service via a number of crafted "KOD" messages.

Improper Input Validation

The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77

CVE-2015-7705 9.8 - Critical - August 07, 2017

The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote attackers to have unspecified impact via a large number of crafted requests.

Improper Input Validation

Use-after-free vulnerability in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7849 8.8 - High - August 07, 2017

Use-after-free vulnerability in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote authenticated users to possibly execute arbitrary code or cause a denial of service (crash) via crafted packets.

Dangling pointer

ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7850 6.5 - Medium - August 07, 2017

ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote authenticated users to cause a denial of service (infinite loop or crash) by pointing the key file at the log file.

Infinite Loop

ntpq in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7852 5.9 - Medium - August 07, 2017

ntpq in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (crash) via crafted mode 6 response packets.

Improper Input Validation

The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7853 9.8 - Critical - August 07, 2017

The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative input value.

Classic Buffer Overflow

The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7855 6.5 - Medium - August 07, 2017

The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value.

Improper Input Validation

Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7871 9.8 - Critical - August 07, 2017

Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.

authentification

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7692 7.5 - High - August 07, 2017

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (crash). NOTE: This vulnerability exists due to an incomplete fix for CVE-2014-9750.

Improper Input Validation

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77

CVE-2015-7691 7.5 - High - August 07, 2017

The crypto_xmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (crash) via crafted packets containing particular autokey operations. NOTE: This vulnerability exists due to an incomplete fix for CVE-2014-9750.

Improper Input Validation

The "pidfile" or "driftfile" directives in NTP ntpd 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77, when ntpd is configured to allow remote configuration, allows remote attackers with an IP address

CVE-2015-7703 7.5 - High - July 24, 2017

The "pidfile" or "driftfile" directives in NTP ntpd 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77, when ntpd is configured to allow remote configuration, allows remote attackers with an IP address that is allowed to send configuration requests, and with knowledge of the remote configuration password to write to arbitrary files via the :config command.

Improper Input Validation

The ULOGTOD function in ntp.d in SNTP before 4.2.7p366 does not properly perform type conversions from a precision value to a double, which

CVE-2015-5219 7.5 - High - July 21, 2017

The ULOGTOD function in ntp.d in SNTP before 4.2.7p366 does not properly perform type conversions from a precision value to a double, which allows remote attackers to cause a denial of service (infinite loop) via a crafted NTP packet.

Incorrect Type Conversion or Cast

ntp_openssl.m4 in ntpd in NTP before 4.2.7p112 allows remote attackers to cause a denial of service (segmentation fault) via a crafted statistics or filegen configuration command

CVE-2015-5195 7.5 - High - July 21, 2017

ntp_openssl.m4 in ntpd in NTP before 4.2.7p112 allows remote attackers to cause a denial of service (segmentation fault) via a crafted statistics or filegen configuration command that is not enabled during compilation.

Improper Input Validation

The log_config_command function in ntp_parser.y in ntpd in NTP before 4.2.7p42

CVE-2015-5194 7.5 - High - July 21, 2017

The log_config_command function in ntp_parser.y in ntpd in NTP before 4.2.7p42 allows remote attackers to cause a denial of service (ntpd crash) via crafted logconfig commands.

Improper Input Validation

Multiple buffer overflows in the ctl_put* functions in NTP before 4.2.8p10 and 4.3.x before 4.3.94

CVE-2017-6458 8.8 - High - March 27, 2017

Multiple buffer overflows in the ctl_put* functions in NTP before 4.2.8p10 and 4.3.x before 4.3.94 allow remote authenticated users to have unspecified impact via a long variable.

Buffer Overflow

NTP before 4.2.8p6 and 4.3.x before 4.3.90, when configured in broadcast mode

CVE-2015-7973 6.5 - Medium - January 30, 2017

NTP before 4.2.8p6 and 4.3.x before 4.3.90, when configured in broadcast mode, allows man-in-the-middle attackers to conduct replay attacks by sniffing the network.

7PK - Security Features

ntpd in NTP before 4.2.8p6 and 4.3.x before 4.3.90

CVE-2015-7977 5.9 - Medium - January 30, 2017

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.

NULL Pointer Dereference

NTP before 4.2.8p6 and 4.3.x before 4.3.90

CVE-2015-7979 7.5 - High - January 30, 2017

NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (client-server association tear down) by sending broadcast packets with invalid authentication to a broadcast client.

Data Processing Errors

NTP before 4.2.8p6 and 4.3.x before 4.3.90

CVE-2015-8138 5.3 - Medium - January 30, 2017

NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to bypass the origin timestamp validation via a packet with an origin timestamp set to zero.

Improper Input Validation

The MATCH_ASSOC function in NTP before version 4.2.8p9 and 4.3.x before 4.3.92

CVE-2016-2518 5.3 - Medium - January 30, 2017

The MATCH_ASSOC function in NTP before version 4.2.8p9 and 4.3.x before 4.3.92 allows remote attackers to cause an out-of-bounds reference via an addpeer request with a large hmode value.

Out-of-bounds Read

The read_mru_list function in NTP before 4.2.8p9

CVE-2016-7434 7.5 - High - January 13, 2017

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.

Improper Input Validation

NTP before 4.2.8p9 allows remote attackers to bypass the origin timestamp protection mechanism via an origin timestamp of zero

CVE-2016-7431 5.3 - Medium - January 13, 2017

NTP before 4.2.8p9 allows remote attackers to bypass the origin timestamp protection mechanism via an origin timestamp of zero. NOTE: this vulnerability exists because of a CVE-2015-8138 regression.

Improper Input Validation

NTP before 4.2.8p9 does not properly perform the initial sync calculations, which allows remote attackers to unspecified impact via unknown vectors, related to a "root distance

CVE-2016-7433 5.3 - Medium - January 13, 2017

NTP before 4.2.8p9 does not properly perform the initial sync calculations, which allows remote attackers to unspecified impact via unknown vectors, related to a "root distance that did not include the peer dispersion."

Incorrect Calculation

NTP before 4.2.8p9 rate limits responses received from the configured sources when rate limiting for all associations is enabled, which

CVE-2016-7426 7.5 - High - January 13, 2017

NTP before 4.2.8p9 rate limits responses received from the configured sources when rate limiting for all associations is enabled, which allows remote attackers to cause a denial of service (prevent responses from the sources) by sending responses with a spoofed source address.

Resource Exhaustion

An integer overflow

CVE-2015-7848 7.5 - High - January 06, 2017

An integer overflow can occur in NTP-dev.4.3.70 leading to an out-of-bounds memory copy operation when processing a specially crafted private mode packet. The crafted packet needs to have the correct message authentication code and a valid timestamp. When processed by the NTP daemon, it leads to an immediate crash.

Integer Overflow or Wraparound

An attacker can spoof a packet from a legitimate ntpd server with an origin timestamp

CVE-2016-1548 7.2 - High - January 06, 2017

An attacker can spoof a packet from a legitimate ntpd server with an origin timestamp that matches the peer->dst timestamp recorded for that server. After making this switch, the client in NTP 4.2.8p4 and earlier and NTPSec aa48d001683e5b791a743ec9c575aaf7d867a2b0c will reject all future legitimate server responses. It is possible to force the victim client to move time after the mode has been changed. ntpq gives no indication that the mode has been switched.

Data Processing Errors

An off-path attacker

CVE-2016-1547 5.3 - Medium - January 06, 2017

An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This is true even if authentication is enabled.

Improper Input Validation

Stay on top of Security Vulnerabilities

Want an email whenever new vulnerabilities are published for Ntp or by Ntp? Click the Watch button to subscribe.

Ntp
Vendor

Ntp
Product

subscribe