CVE-2009-0021

Ntp vulnerability

CVSS

5.0

EPSS

3.2%

EPSS pct

87th

Exploited

No known

NTP 4.2.4 before 4.2.4p5 and 4.2.5 before 4.2.5p150 does not properly check the return value from the OpenSSL EVP_VerifyFinal function, which allows remote attackers to bypass validation of the certificate chain via a malformed SSL/TLS signature for DSA and ECDSA keys, a similar vulnerability to CVE-2008-5077.

Affected vendor

Ntp

Affected product

Ntp

CVSS vector

AV:N/AC:L/Au:N/C:P/I:N/A:N

Weakness type (CWE)

CWE-287 — Improper Authentication

Published

2009-01-07

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no authentication. Successful exploitation leads to partial impact to confidentiality.

Its EPSS score of 3.2% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 87% of all scored CVEs.

Check your external exposure to CVE-2009-0021

Confirm whether Ntp Ntp is running on any internet-facing host or subdomain.
Match discovered service fingerprints against the version affected by CVE-2009-0021.
Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2009-0021

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