ntpd up to 4.2.8 Symmetric Mode code

CVSS Meta Temp Score
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3.8$0-$5k0.00

A vulnerability classified as problematic was found in ntpd up to 4.2.8 (Network Management Software). Affected by this vulnerability is an unknown part of the component Symmetric Mode. The manipulation with an unknown input leads to a code vulnerability. The CWE definition for the vulnerability is CWE-17. As an impact it is known to affect availability. The advisory summarizes:

Affects: All NTP releases starting with at least xntp3.3wy up to but not including ntp-4.2.8p2 where the installation uses symmetric key authentication.

The weakness was published 04/07/2015 by Miroslav Lichvar with Red Hat as Sec 2781 as confirmed advisory (Website). The advisory is shared at support.ntp.org. The public release has been coordinated with the project team. The advisory contains:

Note that for users of autokey, this specific style of MITM attack is simply a long-known potential problem.
This vulnerability is known as CVE-2015-1799 since 02/17/2015. The attack needs to be done within the local network. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The advisory points out:
An attacker knowing that NTP hosts A and B are peering with each other (symmetric association) can send a packet to host A with source address of B which will set the NTP state variables on A to the values sent by the attacker. Host A will then send on its next poll to B a packet with originate timestamp that doesn't match the transmit timestamp of B and the packet will be dropped. If the attacker does this periodically for both hosts, they won't be able to synchronize to each other. This is a known denial-of-service attack, described at https://www.eecis.udel.edu/~mills/onwire.html .

The vulnerability scanner Nessus provides a plugin with the ID 83271 (Amazon Linux AMI : ntp (ALAS-2015-520)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 185103 (HP-UX Running NTP Remote Denial of Service Vulnerability).

Upgrading to version 4.2.8p2 eliminates this vulnerability. The upgrade is hosted for download at ntp.org. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

Configure ntpd with appropriate time sources and monitor ntpd. Alert your staff if problems are detected.

The vulnerability is also documented in the databases at X-Force (102052) and Tenable (83271). Additional details are provided at bugs.ntp.org. Similar entry is available at 74664.

Affected

  • FreeBSD
  • Linux

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 3.8

VulDB Base Score: 4.3
VulDB Temp Score: 3.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Code
CWE: CWE-17
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 83271
Nessus Name: Amazon Linux AMI : ntp (ALAS-2015-520)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: ALAS-2015-520
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: ntpd 4.2.8p2

Timelineinfo

02/17/2015 🔍
04/07/2015 +48 days 🔍
04/07/2015 +0 days 🔍
04/07/2015 +0 days 🔍
04/07/2015 +0 days 🔍
04/08/2015 +1 days 🔍
04/08/2015 +0 days 🔍
05/07/2015 +28 days 🔍
06/02/2015 +26 days 🔍
02/24/2016 +268 days 🔍
05/02/2022 +2258 days 🔍

Sourcesinfo

Advisory: Sec 2781
Researcher: Miroslav Lichvar
Organization: Red Hat
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2015-1799 (🔍)
OVAL: 🔍

CERT VU: 🔍
X-Force: 102052 - NTP symmetric key denial of service
SecurityTracker: 1032031
Vulnerability Center: 56735 - NTP before 4.2.8p2 Remote Spoofing due to a Flow in the \x27symmetric-key\x27 Feature - CVE-2015-1799, Medium
SecurityFocus: 73950 - NTP CVE-2015-1799 Denial of Service Vulnerability

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 04/08/2015 10:23
Updated: 05/02/2022 19:35
Changes: 04/08/2015 10:23 (88), 08/23/2018 08:24 (7), 05/02/2022 19:35 (3)
Complete: 🔍

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