---
title: "Operational Notification: Some releases of BIND 9.12 are too strict"
slug: "some-releases-of-bind-9-12-are-too-strict-when-handling-referrals-with-non-empty-answer-sections"
description: "Operational Notification: Some releases of BIND 9.12 are too strict when handling referrals"
updated: 2018-10-29T18:26:35Z
published: 2018-10-29T18:26:35Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://kb.isc.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Operational Notification: Some releases of BIND 9.12 are too strict when handling referrals

**Posting date:** 19 September 2018

**Program Impacted:** BIND

**Versions affected:** 9.12.0 -> 9.12.2-P1. Also releases 9.13.0 -> 9.13.3 of the 9.13 development branch

#### Description

An unexpected side-effect introduced into the BIND 9.12 branch during code refactoring causes referrals with non-empty answer sections to be treated as errors, potentially preventing resolution of names when it involves referrals from servers providing such responses.

**Impact:** A properly constructed referral should not contain information in the answer section but prior to the BIND 9.12 branch, **named** would tolerate such replies if they were otherwise comprehensible as a referral. Beginning with BIND 9.12.0, such messages were treated as errors, causing a situation where names which could be resolved by prior branches of BIND were no longer resolvable due to the stricter interpretation.

**Workarounds:** none

#### Solution

If you are running a version affected by this bug, you can prevent it by upgrading to a release containing the fix which reverses the change in behavior. The patched version can be downloaded from https://www.isc.org/downloads/.

* BIND 9 version 9.12.2-P2

**Do you still have questions?** Questions regarding this advisory should go to [security-officer@isc.org](mailto:security-officer@isc.org). *To report a new issue, please encrypt your message using security-officer@isc.org's PGP key which can be found here: [https://www.isc.org/downloads/software-support-policy/openpgp-key/](https://www.isc.org/downloads/software-support-policy/openpgp-key). If you are unable to use encrypted email, you may also report new issues at: [https://www.isc.org/community/report-bug/](https://www.isc.org/community/report-bug).* 

**Note:** ISC patches only currently supported versions. When possible we indicate EOL versions affected.  (For current information on which versions are actively supported, please see [https://www.isc.org/downloads/](https://www.isc.org/downloads)). 

**ISC Security Vulnerability Disclosure Policy:** Details of our current security advisory policy and practice can be found here: [ISC Software Defect and Security Vulnerability Disclosure Policy](https://kb.isc.org/docs/aa-00861).

This [Knowledgebase article](https://kb.isc.org/docs/some-releases-of-bind-9-12-are-too-strict-when-handling-referrals-with-non-empty-answer-sections) is the complete and official security advisory document.

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