CVE-2015-7871: Critical severity siemens tim 4r-ie vulnerability
Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.
Other sources
The following flaw was found in ntpd:
An error handling logic error exists within ntpd that manifests due to improper error condition handling associated with certain crypto-NAK packets. An unauthenticated, off-path attacker can force ntpd processes on targeted servers to peer with time sources of the attacker's choosing by transmitting symmetric active crypto-NAK packets to ntpd. This attack bypasses the authentication typically required to establish a peer association and allows an attacker to make arbitrary changes to system time.
External References:
http://talosintel.com/reports/TALOS-2015-0069/ http://support.ntp.org/bin/view/Main/SecurityNotice#October2015NTPSecurityVulner
— Red Hat
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2015-7871?
CVE-2015-7871 has been classified as a medium severity vulnerability due to its potential to allow remote attackers to bypass authentication.
How do I fix CVE-2015-7871?
To fix CVE-2015-7871, you should upgrade to NTP version 4.2.8p4 or higher, or 4.3.77 or higher.
What systems are affected by CVE-2015-7871?
CVE-2015-7871 affects NTP versions 4.2.x prior to 4.2.8p4 and 4.3.x prior to 4.3.77, as well as various products from Siemens and NetApp that utilize these versions.
Is there a workaround for CVE-2015-7871?
There is no specific workaround for CVE-2015-7871; the best course of action is to apply the available updates.
What type of vulnerability is CVE-2015-7871?
CVE-2015-7871 is a cryptographic vulnerability that allows attackers to bypass authentication through the exploitation of faulty error handling in NTP.