ASA-2019-00152 – PowerDNS: Insufficient validation in the HTTP remote backend


Allele Security Alert

ASA-2019-00152

Identifier(s)

ASA-2019-00152, CVE-2019-3871

Title

Insufficient validation in the HTTP remote backend

Vendor(s)

PowerDNS

Product(s)

PowerDNS Authoritative

Affected version(s)

PowerDNS Authoritative up to and including 4.1.6

Fixed version(s)

PowerDNSAuthoritative 4.1.7

Proof of concept

Unknown

Description

An issue has been found in PowerDNS Authoritative Server when the HTTP remote backend is used in RESTful mode (without post=1 set), allowing a remote user to cause the HTTP backend to connect to an attacker-specified host instead of the  configured one, via a crafted DNS query. This can be used to cause a denial of service by preventing the remote backend from getting a response, content spoofing if the attacker can time its own query so that subsequent queries will use an attacker-controlled HTTP server instead of the configured one, and possibly information disclosure if the Authoritative Server has access to internal servers.

Technical details

Unknown

Credits

Adam Dobrawy (HyperOne.com), Frederico Silva (HyperOne.com) and Gregory Brzeski (HyperOne.com)

Reference(s)

PowerDNS Security Advisory 2019-03: Insufficient validation in the HTTP remote backend – PowerDNS Authoritative Server documentation
https://docs.powerdns.com/authoritative/security-advisories/powerdns-advisory-2019-03.html

PowerDNS Security Advisory 2019-03
https://seclists.org/oss-sec/2019/q1/185

HTTP Remote Backend wrong host #7573
https://github.com/PowerDNS/pdns/issues/7573

CVE-2019-3871
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-3871

CVE-2019-3871
https://nvd.nist.gov/vuln/detail/CVE-2019-3871

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Last modified: March 20, 2019

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