CVE-2009-0021

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2009-01-07 · updated 2026-06-16
Weakness: CWE-287

Description

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 products

NTP: through 4.2.4p4; 4.2.0, 4.2.2, 4.2.4p1, 4.2.4p2, 4.2.4p3

References

http://lists.apple.com/archives/security-announce/2009/May/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2009-03/msg00000.html
http://lists.opensuse.org/opensuse-security-announce/2009-04/msg00003.html
http://secunia.com/advisories/33406
http://secunia.com/advisories/33558
http://secunia.com/advisories/33648
http://secunia.com/advisories/34642
http://secunia.com/advisories/35074
http://slackware.com/security/viewer.php?l=slackware-security&y=2009&m=slackware-security.531177
http://support.apple.com/kb/HT3549
http://www.ocert.org/advisories/ocert-2008-016.html
http://www.redhat.com/support/errata/RHSA-2009-0046.html

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