VULNERABILITY INTELLIGENCE

CVE-2021-22212

CVSS score4 MEDIUM
EPSS probability0.52%
CISA KEVNot currently listed
Published2021-06-08
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N

Description

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.

Weakness classification

  • nvd@nist.gov: CWE-327

Primary references