Synopsis
The remote Red Hat host is missing one or more security updates for ntp.
Description
The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2016:0780 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 the fix for CVE-2014-9750 was incomplete: three issues were found in the value length checks in NTP's ntp_crypto.c, where a packet with particular autokey operations that contained malicious data was not always being completely validated. A remote attacker could use a specially crafted NTP packet to crash ntpd. (CVE-2015-7691, CVE-2015-7692, CVE-2015-7702)
* A memory leak flaw was found in ntpd's CRYPTO_ASSOC. If ntpd was configured to use autokey authentication, an attacker could send packets to ntpd that would, after several days of ongoing attack, cause it to run out of memory. (CVE-2015-7701)
* An off-by-one flaw, leading to a buffer overflow, was found in cookedprint functionality of ntpq. A specially crafted NTP packet could potentially cause ntpq to crash. (CVE-2015-7852)
* A NULL pointer dereference flaw was found in the way ntpd processed 'ntpdc reslist' commands that queried restriction lists with a large amount of entries. A remote attacker could potentially use this flaw to crash ntpd. (CVE-2015-7977)
* A stack-based buffer overflow flaw was found in the way ntpd processed 'ntpdc reslist' commands that queried restriction lists with a large amount of entries. A remote attacker could use this flaw to crash ntpd. (CVE-2015-7978)
* It was found that ntpd could crash due to an uninitialized variable when processing malformed logconfig configuration commands. (CVE-2015-5194)
* It was found that ntpd would exit with a segmentation fault when a statistics type that was not enabled during compilation (e.g. timingstats) was referenced by the statistics or filegen configuration command.
(CVE-2015-5195)
* It was discovered that the sntp utility could become unresponsive due to being caught in an infinite loop when processing a crafted NTP packet. (CVE-2015-5219)
* It was found that NTP's :config command could be used to set the pidfile and driftfile paths without any restrictions. A remote attacker could use this flaw to overwrite a file on the file system with a file containing the pid of the ntpd process (immediately) or the current estimated drift of the system clock (in hourly intervals). (CVE-2015-7703)
The CVE-2015-5219 and CVE-2015-7703 issues were discovered by Miroslav Lichvr (Red Hat).
For detailed information on changes in this release, see the Red Hat Enterprise Linux 6.8 Release Notes and Red Hat Enterprise Linux 6.8 Technical Notes linked from the References section.
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.
Solution
Update the RHEL ntp package based on the guidance in RHSA-2016:0780.
Plugin Details
File Name: redhat-RHSA-2016-0780.nasl
Agent: unix
Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus
Risk Information
Vendor
Vendor Severity: Moderate
Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: p-cpe:/a:redhat:enterprise_linux:ntp-doc, cpe:/o:redhat:enterprise_linux:6, p-cpe:/a:redhat:enterprise_linux:ntp, p-cpe:/a:redhat:enterprise_linux:ntp-perl, p-cpe:/a:redhat:enterprise_linux:ntpdate
Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu
Exploit Ease: No known exploits are available
Patch Publication Date: 5/10/2016
Vulnerability Publication Date: 1/30/2017
Reference Information
CVE: CVE-2015-5194, CVE-2015-5195, CVE-2015-5219, CVE-2015-7691, CVE-2015-7692, CVE-2015-7701, CVE-2015-7702, CVE-2015-7703, CVE-2015-7852, CVE-2015-7977, CVE-2015-7978