Unbound < 1.5.1 Delegation Handling Recursive Referral Handling Resource Exhaustion DoS

medium Nessus Plugin ID 87870

Language:

New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote name server is affected by a denial of service vulnerability.

Description

According to its self-reported version number, the remote Unbound DNS resolver is affected by a denial of service vulnerability in the Domain Name Service due to improper handling of a maliciously-constructed zone or queries from a rogue server. An unauthenticated, remote attacker can exploit this, via a specially crafted request, to cause the service to issue unlimited queries in an attempt to follow a delegation, resulting in a denial of service condition.

Solution

Upgrade to Unbound version 1.5.1 or later. Alternatively, apply the patch provided by the vendor.

See Also

https://nlnetlabs.nl/downloads/unbound/CVE-2014-8602.txt

https://nlnetlabs.nl/downloads/unbound/patch_cve_2014_8602.diff

Plugin Details

Severity: Medium

ID: 87870

File Name: unbound_1_5_1.nasl

Version: 1.4

Type: remote

Family: DNS

Published: 1/12/2016

Updated: 11/15/2018

Dependencies: unbound_version.nasl

Configuration: Enable paranoid mode

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:unbound:unbound

Required KB Items: Settings/ParanoidReport, unbound/version

Exploit Ease: No known exploits are available

Patch Publication Date: 12/8/2011

Vulnerability Publication Date: 12/8/2014

Reference Information

CVE: CVE-2014-8602

BID: 71589

CERT: 264212