CVE-2021-22212medium

CVE-2021-22212: medium-severity vulnerability in ntpsec

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4epss 0.5%
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.
CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N
Affected products
NTPsec · ntpsec
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