medium
6.4
CWE
NVD-CWE-Other
Advisory Published
CVE Published
CVE Published
Updated

CVE-2009-3563

First published: Tue Oct 27 2009(Updated: )

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.

Credit: cve@mitre.org cve@mitre.org

Affected SoftwareAffected VersionHow to fix
redhat/ntp<0:4.1.2-6.el3
0:4.1.2-6.el3
redhat/ntp<0:4.2.0.a.20040617-8.el4_8.1
0:4.2.0.a.20040617-8.el4_8.1
redhat/ntp<0:4.2.2p1-9.el5_4.1
0:4.2.2p1-9.el5_4.1
NTP<=4.2.2p4
NTP=4.0.72
NTP=4.0.73
NTP=4.0.90
NTP=4.0.91
NTP=4.0.92
NTP=4.0.93
NTP=4.0.94
NTP=4.0.95
NTP=4.0.96
NTP=4.0.97
NTP=4.0.98
NTP=4.0.99
NTP=4.1.0
NTP=4.1.2
NTP=4.2.0
NTP=4.2.2
NTP=4.2.2p1
NTP=4.2.2p2
NTP=4.2.2p3
NTP=4.2.5

Remedy

http://support.ntp.org/bin/view/Main/SecurityNotice#DoS_attack_from_certain_NTP_mode

Remedy

http://www.debian.org/security/2009/dsa-1948

Remedy

http://www.kb.cert.org/vuls/id/568372

Remedy

http://www.securityfocus.com/bid/37255

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2009-3563?

    CVE-2009-3563 has a severity rating that indicates a denial of service vulnerability due to CPU and bandwidth consumption.

  • How do I fix CVE-2009-3563?

    To fix CVE-2009-3563, upgrade to NTP versions that are patched—specifically 4.2.4p8 or later.

  • What software is affected by CVE-2009-3563?

    CVE-2009-3563 affects various versions of the NTP daemon, specifically those prior to 4.2.4p8 and 4.2.5.

  • What type of attack does CVE-2009-3563 exploit?

    CVE-2009-3563 exploits a vulnerability that allows remote attackers to send spoofed requests causing excessive resource consumption.

  • Is there a workaround for CVE-2009-3563 if I cannot upgrade?

    If upgrading is not possible, restricting access to NTP services or implementing firewall rules may mitigate the risk associated with CVE-2009-3563.

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