Ntpsec
CVE-2021-22212
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A04:2025 - Cryptographic Failures
ASVS 5.0
V11 - Cryptography Approved algorithm selection
|
| Impact | CVSS score of 7.4 (HIGH). Attack characteristics: network attack vector, high complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
ntpkeygen can generate keys that ntpd fails to parse. Rated high severity (CVSS 7.4), this vulnerability is remotely exploitable, no authentication required.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-327. ntpkeygen can generate keys that ntpd fails to parse. NTPsec 1.2.0 allows ntpkeygen to generate keys with '#' characters. ntpd then either pads, shortens the key, or fails to load these keys entirely, depending on the key type and the placement of the '#'. This results in the administrator not being able to use the keys as expected or the keys are shorter than expected and easier to brute-force, possibly resulting in MITM attacks between ntp clients and ntp servers. For short AES128 keys, ntpd generates a warning that it is padding them. Affected products include: Ntpsec, Fedoraproject Fedora.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
ntpkeygen can generate keys that ntpd fails to parse. NTPsec 1.2.0 allows ntpkeygen to generate keys with '#' characters. ntpd then either pads, shortens the key, or fails to load these keys entirely, depending on the key type and the placement of the '#'. This results in the administrator not being able to use the keys as expected or the keys are shorter than expected and easier to brute-force, possibly resulting in MITM attacks between ntp clients and ntp servers. For short AES128 keys, ntpd generates a warning that it is padding them.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)NVD
An issue was discovered in NTPsec before 1.1.3. Rated critical severity (CVSS 9.1), this vulnerability is remotely explo
An issue was discovered in NTPsec before 1.1.3. Rated critical severity (CVSS 9.1), this vulnerability is remotely explo
An issue was discovered in NTPsec before 1.1.3. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploit
An issue was discovered in NTPsec before 1.1.3. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploit
Arbitrary shell command execution in gpsd's gpsprof profiling tool (through release-3.27.5) allows an attacker who contr
Remote denial of service in NTPsec ntpd 1.1.4 through 1.2.5 lets an unauthenticated network attacker crash the daemon by
Denial of service in NTPsec ntpd 1.1.4 through 1.2.5 allows a remote unauthenticated attacker to terminate the daemon by
ntpd will crash if the server is not NTS-enabled (no certificate) and it receives an NTS-enabled client request (mode 3)
Heap-based memory corruption in NTPsec ntpd before 1.2.6 affects deployments that explicitly enable the non-default JJY
Out-of-bounds read in NTPsec ntpd before 1.2.6 can crash the daemon or disclose limited memory when an attacker controls
Buffer overflow in NTPsec's Zyfer refclock driver crashes the ntpd daemon on affected systems running versions prior to
ntpd in NTP 4.2.8p3 and NTPsec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 relies on the underlying operating system to pro
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB