RHSA-2009:1651: Moderate: ntp security update

Published Dec 8, 2009
·
Updated

The Network Time Protocol (NTP) is used to synchronize a computer's timewith a referenced time source.Robin Park and Dmitri Vinokurov discovered a flaw in the way ntpd handledcertain malformed NTP packets. ntpd logged information about all suchpackets and replied with an NTP packet that was treated as malformed whenreceived by another ntpd. A remote attacker could use this flaw to createan NTP packet reply loop between two ntpd servers via a malformed packetwith a spoofed source IP address and port, causing ntpd on those servers touse excessive amounts of CPU time and fill disk space with log messages.(CVE-2009-3563)A buffer overflow flaw was found in the ntpq diagnostic command. Amalicious, remote server could send a specially-crafted reply to an ntpqrequest that could crash ntpq or, potentially, execute arbitrary code withthe privileges of the user running the ntpq command. (CVE-2009-0159)All ntp users are advised to upgrade to this updated package, whichcontains backported patches to resolve these issues. After installing theupdate, the ntpd daemon will restart automatically.

Affected Software

1 affected component
Network Time Protocol (NTP) NTP

Remediation

Event History

Dec 8, 2009
Advisory Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2009:1651?

The severity of RHSA-2009:1651 is classified as moderate.

2

How do I fix RHSA-2009:1651?

To fix RHSA-2009:1651, update the Network Time Protocol (NTP) daemon to the latest version provided by your operating system vendor.

3

What specific vulnerability does RHSA-2009:1651 address?

RHSA-2009:1651 addresses a flaw in how ntpd handles malformed NTP packets.

4

Are there any workarounds for RHSA-2009:1651?

Temporary workarounds for RHSA-2009:1651 may include restricting NTP access to trusted sources only.

5

Who reported the vulnerability in RHSA-2009:1651?

The vulnerability in RHSA-2009:1651 was discovered by researchers Robin Park and Dmitri Vinokurov.

Contact

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