CVE-2009-3563

Severity: medium (CVSS 6.4 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 32.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2009-12-09 · updated 2026-06-16

Description

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.

Affected products

NTP: through 4.2.2p4; 4.0.72, 4.0.73, 4.0.90, 4.0.91, 4.0.92, 4.0.93 (+14)

References

http://aix.software.ibm.com/aix/efixes/security/xntpd_advisory.asc
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=560074
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10673
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10691
http://lists.vmware.com/pipermail/security-announce/2010/000082.html
http://marc.info/?l=bugtraq&m=130168580504508&w=2
http://marc.info/?l=bugtraq&m=136482797910018&w=2
http://secunia.com/advisories/37629
http://secunia.com/advisories/37922
http://secunia.com/advisories/38764
http://secunia.com/advisories/38794

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