VDB-123892 · CVE-2016-7074 · Nessus 96849

PowerDNS/PowerDNS Recursor TSIG Signature input validation

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.5	$0-$5k	0.00

Summaryinfo

A vulnerability was found in PowerDNS and PowerDNS Recursor. It has been declared as critical. Affected is an unknown function of the component TSIG Signature Handler. Executing a manipulation can lead to input validation. This vulnerability is tracked as CVE-2016-7074. The attack can be launched remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in PowerDNS and PowerDNS Recursor (Domain Name Software) (version now known). It has been declared as critical. This vulnerability affects some unknown processing of the component TSIG Signature Handler. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An issue has been found in PowerDNS before 3.4.11 and 4.0.2, and PowerDNS recursor before 4.0.4, allowing an attacker in position of man-in-the-middle to alter the content of an AXFR because of insufficient validation of TSIG signatures. A missing check that the TSIG record is the last one, leading to the possibility of parsing records that are not covered by the TSIG signature.

The bug was discovered 12/15/2016. The weakness was disclosed 09/11/2018 as not defined bug report (Bugzilla). The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2016-7074 since 08/23/2016. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 44 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 96849 (Fedora 25 : pdns (2017-cbd5501d31)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 175940 (Debian Security Update for pdns (DSA 3764-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (96849). The entries VDB-123797, VDB-123888, VDB-123891 and VDB-126386 are pretty similar. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Domain Name Software

Name

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CNA Base Score: 5.3
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 96849
Nessus Name: Fedora 25 : pdns (2017-cbd5501d31)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for pdns FEDORA-2017-cbd5501d31
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/23/2016 🔍
12/15/2016 +114 days 🔍
01/27/2017 +43 days 🔍
01/30/2017 +2 days 🔍
09/11/2018 +588 days 🔍
09/11/2018 +0 days 🔍
09/12/2018 +1 days 🔍
05/08/2023 +1699 days 🔍