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 bandwidth…
- 6.4MediumCVSS base score
- 32.1%Exploitation in 30 daysEPSS · top 1.7% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- 1Public exploitsMetasploit, Nuclei and Exploit-DB
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module for it.
Show the exploits1
Metasploit modules1 module
- NTP.org ntpd Reserved Mode Denial of Service (Metasploit module) (opens in a new tab)
auxiliary/dos/ntp/ntpd_reserved_dosRank normaldisclosed 4 Oct 2009
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By mitre
- 2 months later
· 2 months later
Published
- 15 years later
· 15 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium6.4 | AV:N/AC:L/Au:N/C:N/I:P/A:P |
- EPSS (exploitation in 30 days)
- 32.1% · top 1.7% of all CVEs (10 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.4.
Affected products
n/a
- affected n/a
References
42
- VU#568372 (opens in a new tab)third-party-advisoryx_transferred
- 38832 (opens in a new tab)third-party-advisoryx_transferred
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10673 (opens in a new tab)x_transferred
- oval:org.mitre.oval:def:11225 (opens in a new tab)vdb-entrysignaturex_transferred
- http://support.avaya.com/css/P8/documents/100071808 (opens in a new tab)x_transferred
- 38794 (opens in a new tab)third-party-advisoryx_transferred
- [security-announce] 20100303 VMSA-2010-0004 ESX Service Console and vMA third party updates (opens in a new tab)mailing-listx_transferred
- FEDORA-2009-13121 (opens in a new tab)vendor-advisoryx_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=531213 (opens in a new tab)x_transferred
- 38764 (opens in a new tab)third-party-advisoryx_transferred
- http://support.ntp.org/bin/view/Main/SecurityNotice#DoS_attack_from_certain_NTP_mode (opens in a new tab)x_transferred
- http://www.kb.cert.org/vuls/id/MAPG-7X7V6J (opens in a new tab)x_transferred
- oval:org.mitre.oval:def:19376 (opens in a new tab)vdb-entrysignaturex_transferred
- 37255 (opens in a new tab)vdb-entryx_transferred
- SSRT101144 (opens in a new tab)vendor-advisoryx_transferred
- 39593 (opens in a new tab)third-party-advisoryx_transferred
- IZ71047 (opens in a new tab)vendor-advisoryx_transferred
- ADV-2010-0993 (opens in a new tab)vdb-entryx_transferred
- DSA-1948 (opens in a new tab)vendor-advisoryx_transferred
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=560074 (opens in a new tab)x_transferred
- http://aix.software.ibm.com/aix/efixes/security/xntpd_advisory.asc (opens in a new tab)x_transferred
- HPSBUX02639 (opens in a new tab)vendor-advisoryx_transferred
- 1021781 (opens in a new tab)vendor-advisoryx_transferred
- IZ68659 (opens in a new tab)vendor-advisoryx_transferred
- https://support.ntp.org/bugs/show_bug.cgi?id=1331 (opens in a new tab)x_transferred
- oval:org.mitre.oval:def:7076 (opens in a new tab)vdb-entrysignaturex_transferred
- 37922 (opens in a new tab)third-party-advisoryx_transferred
- 38834 (opens in a new tab)third-party-advisoryx_transferred
- FEDORA-2009-13090 (opens in a new tab)vendor-advisoryx_transferred
- http://security-tracker.debian.org/tracker/CVE-2009-3563 (opens in a new tab)x_transferred
- 1023298 (opens in a new tab)vdb-entryx_transferred
- oval:org.mitre.oval:def:12141 (opens in a new tab)vdb-entrysignaturex_transferred
- RHSA-2009:1651 (opens in a new tab)vendor-advisoryx_transferred
- 37629 (opens in a new tab)third-party-advisoryx_transferred
- RHSA-2010:0095 (opens in a new tab)vendor-advisoryx_transferred
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10691 (opens in a new tab)x_transferred
- [announce] 20091208 NTP 4.2.4p8 Released (opens in a new tab)mailing-listx_transferred
- ADV-2010-0510 (opens in a new tab)vdb-entryx_transferred
- RHSA-2009:1648 (opens in a new tab)vendor-advisoryx_transferred
- http://www.kb.cert.org/vuls/id/MAPG-7X7VD7 (opens in a new tab)x_transferred
- ADV-2010-0528 (opens in a new tab)vdb-entryx_transferred
- VU#417980 (opens in a new tab)third-party-advisoryx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2009-3544 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2009-3563)Record last updated .