CVE-2009-0021
MEDIUM · CVSS 5.0EPSS 3.2%EU EUVD
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.
Key facts
- CVSS score
- 5.0 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:L/Au:N/C:P/I:N/A:N- Weakness (CWE)
- CWE-287
- EPSS score
- 3.2% (88th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2009-0034)
- Published
- January 7, 2009
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2009-0034 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- ntp / ntp
- ntp / ntp
- ntp / ntp
- ntp / ntp
- ntp / ntp
- ntp / ntp
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(Vendor Advisory)
- http://secunia.com/advisories/33558(Vendor Advisory)
- http://secunia.com/advisories/33648(Vendor Advisory)
- http://secunia.com/advisories/34642(Vendor Advisory)
- http://secunia.com/advisories/35074(Vendor Advisory)
- 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
- http://www.securityfocus.com/archive/1/499827/100/0/threaded
- http://www.securitytracker.com/id?1021533
- http://www.us-cert.gov/cas/techalerts/TA09-133A.html(US Government Resource)
- http://www.vupen.com/english/advisories/2009/0042(Vendor Advisory)
- http://www.vupen.com/english/advisories/2009/1297(Vendor Advisory)
- https://lists.ntp.org/pipermail/announce/2009-January/000055.html
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10035
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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