ID

VAR-201510-0706

CVE

CVE-2014-9751

TITLE

NTP Project Network Time Protocol daemon (ntpd) contains multiple vulnerabilities (Updated)

DESCRIPTION

The read_network_packet function in ntp_io.c in ntpd in NTP 4.x before 4.2.8p1 on Linux and OS X does not properly determine whether a source IP address is an IPv6 loopback address, which makes it easier for remote attackers to spoof restricted packets, and read or write to the runtime state, by leveraging the ability to reach the ntpd machine's network interface with a packet from the ::1 address. The NTP Project ntpd version 4.2.7 and pervious versions contain several vulnerabilities. ntp-keygen prior to version 4.2.7p230 also uses a non-cryptographic random number generator when generating symmetric keys. These vulnerabilities may affect ntpd acting as a server or client. Supplementary information : CWE Vulnerability type by CWE-17: Code ( code ) Has been identified. NTP is prone to a security-bypass vulnerability. Attackers can exploit this issue to bypass certain security restrictions and to perform unauthorized actions; this may aid in launching further attacks. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ===================================================================== Red Hat Security Advisory Synopsis: Moderate: ntp security, bug fix, and enhancement update Advisory ID: RHSA-2015:2231-04 Product: Red Hat Enterprise Linux Advisory URL: https://rhn.redhat.com/errata/RHSA-2015-2231.html Issue date: 2015-11-19 CVE Names: CVE-2014-9297 CVE-2014-9298 CVE-2014-9750 CVE-2014-9751 CVE-2015-1798 CVE-2015-1799 CVE-2015-3405 ===================================================================== 1. Summary: Updated ntp packages that fix multiple security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section. 2. Relevant releases/architectures: Red Hat Enterprise Linux Client (v. 7) - x86_64 Red Hat Enterprise Linux Client Optional (v. 7) - noarch, x86_64 Red Hat Enterprise Linux ComputeNode (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode Optional (v. 7) - noarch, x86_64 Red Hat Enterprise Linux Server (v. 7) - aarch64, ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 7) - aarch64, noarch, ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 7) - x86_64 Red Hat Enterprise Linux Workstation Optional (v. 7) - noarch, x86_64 3. Description: 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. It was found that because NTP's access control was based on a source IP address, an attacker could bypass source IP restrictions and send malicious control and configuration packets by spoofing ::1 addresses. (CVE-2014-9298, CVE-2014-9751) A denial of service flaw was found in the way NTP hosts that were peering with each other authenticated themselves before updating their internal state variables. An attacker could send packets to one peer host, which could cascade to other peers, and stop the synchronization process among the reached peers. (CVE-2015-1799) A flaw was found in the way the ntp-keygen utility generated MD5 symmetric keys on big-endian systems. An attacker could possibly use this flaw to guess generated MD5 keys, which could then be used to spoof an NTP client or server. (CVE-2015-3405) A stack-based buffer overflow was found in the way the NTP autokey protocol was implemented. (CVE-2014-9297, CVE-2014-9750) It was found that ntpd did not check whether a Message Authentication Code (MAC) was present in a received packet when ntpd was configured to use symmetric cryptographic keys. A man-in-the-middle attacker could use this flaw to send crafted packets that would be accepted by a client or a peer without the attacker knowing the symmetric key. (CVE-2015-1798) The CVE-2015-1798 and CVE-2015-1799 issues were discovered by Miroslav Lichvár of Red Hat. Bug fixes: * The ntpd service truncated symmetric keys specified in the key file to 20 bytes. As a consequence, it was impossible to configure NTP authentication to work with peers that use longer keys. With this update, the maximum key length has been changed to 32 bytes. (BZ#1191111) * The ntpd service could previously join multicast groups only when starting, which caused problems if ntpd was started during system boot before network was configured. With this update, ntpd attempts to join multicast groups every time network configuration is changed. (BZ#1207014) * Previously, the ntp-keygen utility used the exponent of 3 when generating RSA keys. Consequently, generating RSA keys failed when FIPS mode was enabled. With this update, ntp-keygen has been modified to use the exponent of 65537, and generating keys in FIPS mode now works as expected. (BZ#1191116) * The ntpd service dropped incoming NTP packets if their source port was lower than 123 (the NTP port). With this update, ntpd no longer checks the source port number, and clients behind NAT are now able to correctly synchronize with the server. (BZ#1171640) Enhancements: * This update adds support for configurable Differentiated Services Code Points (DSCP) in NTP packets, simplifying configuration in large networks where different NTP implementations or versions are using different DSCP values. (BZ#1202828) * This update adds the ability to configure separate clock stepping thresholds for each direction (backward and forward). Use the "stepback" and "stepfwd" options to configure each threshold. (BZ#1193154) * Support for nanosecond resolution has been added to the Structural Health Monitoring (SHM) reference clock. Prior to this update, when a Precision Time Protocol (PTP) hardware clock was used as a time source to synchronize the system clock, the accuracy of the synchronization was limited due to the microsecond resolution of the SHM protocol. The nanosecond extension in the SHM protocol now allows sub-microsecond synchronization of the system clock. (BZ#1117702) All ntp users are advised to upgrade to these updated packages, which contain backported patches to correct these issues and add these enhancements. 4. Solution: Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258 5. Bugs fixed (https://bugzilla.redhat.com/): 1117702 - SHM refclock doesn't support nanosecond resolution 1122012 - SHM refclock allows only two units with owner-only access 1171640 - NTP drops requests when sourceport is below 123 1180721 - ntp: mreadvar command crash in ntpq 1184572 - CVE-2014-9298 CVE-2014-9751 ntp: drop packets with source address ::1 1184573 - CVE-2014-9297 CVE-2014-9750 ntp: vallen in extension fields are not validated 1191108 - ntpd should warn when monitoring facility can't be disabled due to restrict configuration 1191122 - ntpd -x steps clock on leap second 1193154 - permit differential fwd/back threshold for step vs. slew [PATCH] 1199430 - CVE-2015-1798 ntp: ntpd accepts unauthenticated packets with symmetric key crypto 1199435 - CVE-2015-1799 ntp: authentication doesn't protect symmetric associations against DoS attacks 1210324 - CVE-2015-3405 ntp: ntp-keygen may generate non-random symmetric keys on big-endian systems 6. Package List: Red Hat Enterprise Linux Client (v. 7): Source: ntp-4.2.6p5-22.el7.src.rpm x86_64: ntp-4.2.6p5-22.el7.x86_64.rpm ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm ntpdate-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux Client Optional (v. 7): noarch: ntp-doc-4.2.6p5-22.el7.noarch.rpm ntp-perl-4.2.6p5-22.el7.noarch.rpm x86_64: ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm sntp-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux ComputeNode (v. 7): Source: ntp-4.2.6p5-22.el7.src.rpm x86_64: ntp-4.2.6p5-22.el7.x86_64.rpm ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm ntpdate-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux ComputeNode Optional (v. 7): noarch: ntp-doc-4.2.6p5-22.el7.noarch.rpm ntp-perl-4.2.6p5-22.el7.noarch.rpm x86_64: ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm sntp-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux Server (v. 7): Source: ntp-4.2.6p5-22.el7.src.rpm aarch64: ntp-4.2.6p5-22.el7.aarch64.rpm ntp-debuginfo-4.2.6p5-22.el7.aarch64.rpm ntpdate-4.2.6p5-22.el7.aarch64.rpm ppc64: ntp-4.2.6p5-22.el7.ppc64.rpm ntp-debuginfo-4.2.6p5-22.el7.ppc64.rpm ntpdate-4.2.6p5-22.el7.ppc64.rpm ppc64le: ntp-4.2.6p5-22.el7.ppc64le.rpm ntp-debuginfo-4.2.6p5-22.el7.ppc64le.rpm ntpdate-4.2.6p5-22.el7.ppc64le.rpm s390x: ntp-4.2.6p5-22.el7.s390x.rpm ntp-debuginfo-4.2.6p5-22.el7.s390x.rpm ntpdate-4.2.6p5-22.el7.s390x.rpm x86_64: ntp-4.2.6p5-22.el7.x86_64.rpm ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm ntpdate-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux Server Optional (v. 7): aarch64: ntp-debuginfo-4.2.6p5-22.el7.aarch64.rpm sntp-4.2.6p5-22.el7.aarch64.rpm noarch: ntp-doc-4.2.6p5-22.el7.noarch.rpm ntp-perl-4.2.6p5-22.el7.noarch.rpm ppc64: ntp-debuginfo-4.2.6p5-22.el7.ppc64.rpm sntp-4.2.6p5-22.el7.ppc64.rpm ppc64le: ntp-debuginfo-4.2.6p5-22.el7.ppc64le.rpm sntp-4.2.6p5-22.el7.ppc64le.rpm s390x: ntp-debuginfo-4.2.6p5-22.el7.s390x.rpm sntp-4.2.6p5-22.el7.s390x.rpm x86_64: ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm sntp-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux Workstation (v. 7): Source: ntp-4.2.6p5-22.el7.src.rpm x86_64: ntp-4.2.6p5-22.el7.x86_64.rpm ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm ntpdate-4.2.6p5-22.el7.x86_64.rpm Red Hat Enterprise Linux Workstation Optional (v. 7): noarch: ntp-doc-4.2.6p5-22.el7.noarch.rpm ntp-perl-4.2.6p5-22.el7.noarch.rpm x86_64: ntp-debuginfo-4.2.6p5-22.el7.x86_64.rpm sntp-4.2.6p5-22.el7.x86_64.rpm These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/ 7. References: https://access.redhat.com/security/cve/CVE-2014-9297 https://access.redhat.com/security/cve/CVE-2014-9298 https://access.redhat.com/security/cve/CVE-2014-9750 https://access.redhat.com/security/cve/CVE-2014-9751 https://access.redhat.com/security/cve/CVE-2015-1798 https://access.redhat.com/security/cve/CVE-2015-1799 https://access.redhat.com/security/cve/CVE-2015-3405 https://access.redhat.com/security/updates/classification/#moderate 8. Contact: The Red Hat security contact is <secalert@redhat.com>. More contact details at https://access.redhat.com/security/team/contact/ Copyright 2015 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iD4DBQFWTkFJXlSAg2UNWIIRAphzAKCRHDVdHI5OvJ8glkXYLBwyQgeyvwCYmTV3 1hLTu5I/PUzWOnD8rRIlZQ== =sWdG -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://www.redhat.com/mailman/listinfo/rhsa-announce. An attacker could use a specially crafted package to cause ntpd to crash if: * ntpd enabled remote configuration * The attacker had the knowledge of the configuration password * The attacker had access to a computer entrusted to perform remote configuration Note that remote configuration is disabled by default in NTP. CVE-2015-5194 It was found that ntpd could crash due to an uninitialized variable when processing malformed logconfig configuration commands. CVE-2015-5195 It was found that ntpd exits with a segmentation fault when a statistics type that was not enabled during compilation (e.g. timingstats) is referenced by the statistics or filegen configuration command CVE-2015-5219 It was discovered that sntp program would hang in an infinite loop when a crafted NTP packet was received, related to the conversion of the precision value in the packet to double. CVE-2015-5300 It was found that ntpd did not correctly implement the -g option: Normally, ntpd exits with a message to the system log if the offset exceeds the panic threshold, which is 1000 s by default. This option allows the time to be set to any value without restriction; however, this can happen only once. If the threshold is exceeded after that, ntpd will exit with a message to the system log. This option can be used with the -q and -x options. ntpd could actually step the clock multiple times by more than the panic threshold if its clock discipline doesn't have enough time to reach the sync state and stay there for at least one update. If a man-in-the-middle attacker can control the NTP traffic since ntpd was started (or maybe up to 15-30 minutes after that), they can prevent the client from reaching the sync state and force it to step its clock by any amount any number of times, which can be used by attackers to expire certificates, etc. This is contrary to what the documentation says. Normally, the assumption is that an MITM attacker can step the clock more than the panic threshold only once when ntpd starts and to make a larger adjustment the attacker has to divide it into multiple smaller steps, each taking 15 minutes, which is slow. CVE-2015-7691, CVE-2015-7692, CVE-2015-7702 It was found that the fix for CVE-2014-9750 was incomplete: three issues were found in the value length checks in ntp_crypto.c, where a packet with particular autokey operations that contained malicious data was not always being completely validated. Receipt of these packets can cause ntpd to crash. CVE-2015-7701 A memory leak flaw was found in ntpd's CRYPTO_ASSOC. CVE-2015-7703 Miroslav Lichvar of Red Hat found that the :config command can 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). For example: ntpq -c ':config pidfile /tmp/ntp.pid' ntpq -c ':config driftfile /tmp/ntp.drift' In Debian ntpd is configured to drop root privileges, which limits the impact of this issue. CVE-2015-7704 If ntpd as an NTP client receives a Kiss-of-Death (KoD) packet from the server to reduce its polling rate, it doesn't check if the originate timestamp in the reply matches the transmit timestamp from its request. An off-path attacker can send a crafted KoD packet to the client, which will increase the client's polling interval to a large value and effectively disable synchronization with the server. CVE-2015-7850 An exploitable denial of service vulnerability exists in the remote configuration functionality of the Network Time Protocol. A specially crafted configuration file could cause an endless loop resulting in a denial of service. An attacker could provide a the malicious configuration file to trigger this vulnerability. CVE-2015-7852 A potential off by one vulnerability exists in the cookedprint functionality of ntpq. A specially crafted buffer could cause a buffer overflow potentially resulting in null byte being written out of bounds. CVE-2015-7855 It was found that NTP's decodenetnum() would abort with an assertion failure when processing a mode 6 or mode 7 packet containing an unusually long data value where a network address was expected. This could allow an authenticated attacker to crash ntpd. CVE-2015-7871 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. For the oldstable distribution (wheezy), these problems have been fixed in version 1:4.2.6.p5+dfsg-2+deb7u6. For the stable distribution (jessie), these problems have been fixed in version 1:4.2.6.p5+dfsg-7+deb8u1. For the testing distribution (stretch), these problems have been fixed in version 1:4.2.8p4+dfsg-3. For the unstable distribution (sid), these problems have been fixed in version 1:4.2.8p4+dfsg-3. We recommend that you upgrade your ntp packages

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

THREAT TYPE

remote

TYPE

Input Validation Error

CONFIGURATIONS

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Harlan Stenn

SOURCES

LAST UPDATE DATE

2024-11-23T21:03:43.589000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE