Multiple NTP Denial of Service Security Advisories

Number: AV15-100
Date: 22 October 2015


The purpose of this advisory is to bring attention to multiple NTP vulnerability updates.


The NTP project has released version ntp-4.2.8p4 on October 21st, 2015, which fixed 13 vulnerabilities and 3 bugs in their software.

The vulnerabilities can be leveraged to affect the NTP daemon in the following ways:

Arbitrary change to the system time
Memory Corruption via buffer overflow
Denial of Service: Crash or enter an infinite loop
Directory Traversal / File overwrite

Suggested Action

CCIRC recommends that system administrators test and deploy the vendor-released updates to affected applications accordingly.


Note to Readers

In support of Public Safety's mission to build a safe and resilient Canada, CCIRC's mandate is to help ensure the security and resilience of the vital non-federal government cyber systems that underpin Canada's national security, public safety and economic prosperity. As Canada's computer security incident response team, CCIRC is Canada's national coordination centre for the prevention and mitigation of, preparedness for, response to, and recovery from cyber incidents on non-federal government systems. It does this by providing authoritative advice and support, and coordinating information sharing and incident response.

Please note, CCIRC PGP key has recently been updated.

For general information, please contact Public Safety Canada's Public Affairs division at:

Telephone: 613-944-4875 or 1-800-830-3118
Fax: 613-998-9589

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