This issue can affect any product or platform running NTP.org’s NTP daemon.
NTP.org published a security advisory for thirteen vulnerabilities in NTP software on Oct 21st, 2015. These vulnerabilities may allow remote unauthenticated attackers to cause Denial(s) of Service(s), disruption of service(s) by modification of time stamps being issued by the NTP server from malicious NTP crafted packets, including maliciously crafted NTP authentication packets and disclosure of information. This can impact DNS services, as well as certificate chains, such as those used in SSL/https communications and allow attackers to maliciously inject invalid certificates as valid which clients would accept as valid.Junos OSNTP is not enabled in Junos by default. When NTP is enabled within the [edit system ntp] hierarchy level of the Junos configuration Junos OS may be impacted by these vulnerabilities.If unwanted NTP requests come into a Junos device, the NTP process may process these requests as valid NTP incoming packets. On the SRX Series platform, NTP requests coming in from security zones to the firewall self-traffic are dropped by default unless the ‘host-inbound-traffic’ for ‘protocol ntp’ is explicitly enabled.These issues have been assigned CVE-2015-7871 CVE-2015-7855 CVE-2015-7854 CVE-2015-7853 CVE-2015-7852 CVE-2015-7851 CVE-2015-7850 CVE-2015-7849 CVE-2015-7848 CVE-2015-7701 CVE-2015-7703 CVE-2015-7704 CVE-2015-7705 CVE-2015-7691 CVE-2015-7692 CVE-2015-7702.These issues are being tracked as PR 1132181 for Junos OS.KB16765 – “In which releases are vulnerabilities fixed?” describes which release vulnerabilities are fixed as per our End of Engineering and End of Life support policies.Additional platforms and products are still being reviewed.This section will be updated as additional fixes for the vulnerabilities are available.Juniper has published JSA10613 and JSA10663 previously to mitigate attacks and exploits against NTP. To mitigate risk of NTP exploits, customers should read and follow the workaround sections of these JSA’s.To mitigate these exploits:Authenticate with only trusted higher-stratum servers e.g. if your stratum is 10, authenticate to only trusted stratum 0 – 9 servers.Limit the attack surface by implementing firewall filters to only accept NTP authentication messages from trusted servers.Some evidence exists that retrieval of time services from Non-NTP.org NTP-based servers may mitigate these currently-disclosed risks, but is not guaranteed. If your NTP server is a high level stratum; e.g. stratum 0 or 1; open NTP server, no known workarounds exists.Customers are urged to apply the updates as they become available and follow the Solution section.How to obtain fixed software:Security vulnerabilities in Junos are fixed in the next available Maintenance Release of each supported Junos version. In some cases, a Maintenance Release is not planned to be available in an appropriate time-frame. For these cases, Service Releases are made available in order to be more timely. Security Advisory and Security Notices will indicate which Maintenance and Service Releases contain fixes for the issues described. Upon request to JTAC, customers will be provided download instructions for a Service Release. Although Juniper does not provide formal Release Note documentation for a Service Release, a list of “PRs fixed” can be provided on request. Modification History: 2015-10-23: Initial publication
Information for how Juniper Networks uses CVSS can be found at KB16446 “Common Vulnerability Scoring System (CVSS) and Juniper’s Security Advisories”