Unbound < 1.5.1 Delegation Handling Recursive Referral Handling Resource Exhaustion DoS

Medium Nessus Plugin ID 87870

New! Vulnerability Priority Rating (VPR)

Tenable calculates a dynamic VPR for every vulnerability. VPR combines vulnerability information with threat intelligence and machine learning algorithms to predict which vulnerabilities are most likely to be exploited in attacks. Read more about what VPR is and how it's different from CVSS.

VPR Score: 3.6


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


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.


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

See Also



Plugin Details

Severity: Medium

ID: 87870

File Name: unbound_1_5_1.nasl

Version: 1.4

Type: remote

Family: DNS

Published: 2016/01/12

Updated: 2018/11/15

Dependencies: 87872

Configuration: Enable paranoid mode

Risk Information

Risk Factor: Medium

VPR Score: 3.6

CVSS v2.0

Base Score: 4.3

Temporal Score: 3.2

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:unbound:unbound

Required KB Items: Settings/ParanoidReport, unbound/version

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2011/12/08

Vulnerability Publication Date: 2014/12/08

Reference Information

CVE: CVE-2014-8602

BID: 71589

CERT: 264212