The remote Redhat Enterprise Linux 6 / 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2016:1141 advisory.

    The Network Time Protocol (NTP) is used to synchronize a computer's time with another referenced time     source. These packages include the ntpd service which continuously adjusts system time and utilities used     to query and configure the ntpd service.

    Security Fix(es):

    * It was found that when NTP was configured in broadcast mode, a remote attacker could broadcast packets     with bad authentication to all clients. The clients, upon receiving the malformed packets, would break the     association with the broadcast server, causing them to become out of sync over a longer period of time.
    (CVE-2015-7979)

    * A denial of service flaw was found in the way NTP handled preemptable client associations. A remote     attacker could send several crypto NAK packets to a victim client, each with a spoofed source address of     an existing associated peer, preventing that client from synchronizing its time. (CVE-2016-1547)

    * It was found that an ntpd client could be forced to change from basic client/server mode to the     interleaved symmetric mode. A remote attacker could use a spoofed packet that, when processed by an ntpd     client, would cause that client to reject all future legitimate server responses, effectively disabling     time synchronization on that client. (CVE-2016-1548)

    * A flaw was found in the way NTP's libntp performed message authentication. An attacker able to observe     the timing of the comparison function used in packet authentication could potentially use this flaw to     recover the message digest. (CVE-2016-1550)

    * An out-of-bounds access flaw was found in the way ntpd processed certain packets. An authenticated     attacker could use a crafted packet to create a peer association with hmode of 7 and larger, which could     potentially (although highly unlikely) cause ntpd to crash. (CVE-2016-2518)

    The CVE-2016-1548 issue was discovered by Miroslav Lichvar (Red Hat).

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

RHEL 6 / 7 : ntp (RHSA-2016:1141)

high Nessus Plugin ID 91420

Version 2.17