Home/CVE/ntp_request.c in ntpd in NTP before 4.2.4p8, and 4.2.5, allows remote attackers to cause a denial of service (CPU and ba
CVE

CVE-2009-3563

ntp_request.c in ntpd in NTP before 4.2.4p8, and 4.2.5, allows remote attackers to cause a denial of service (CPU and ba

ntp_request.c in ntpd in NTP before 4.2.4p8, and 4.2.5, allows remote attackers to cause a denial of service (CPU and bandwidth consumption) by using MODE_PRIVATE to send a spoofed (1) request or (2) response packet that triggers a continuous exchange of MODE_PRIVATE error responses between two NTP daemons.

MEDIUM · CVSS 6.4 EPSS 0.81107
Act now
  • EPSS ≥ 0.50 - high probability of exploitation in the next 30 days
  • EPSS percentile: top 1% of all CVEs by exploitation likelihood
Sigma rules0 YARA rules0

Affected Products & Versions

2
ntp<= 4.2.2p4
ntpall versions

Scoring & Timeline

6.4
MEDIUM · CVSS v2 (legacy) · cve@mitre.org
View on NVD
This CVE predates CVSS v3; the legacy v2 score is shown so triage still has a severity to work with.
v2 Vector
AV:N/AC:L/Au:N/C:N/I:P/A:P
Published to NVD09 Dec 2009 · 06:30 PM

Vendor Advisories

4
rhsaRHSA-2010:0095Important
rhsaRHSA-2009:1648Moderate
rhsaRHSA-2009:1651Moderate
🔗

References & Sources

43
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
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