CVE-2018-5741: Update policies krb5-subdomain and ms-subdomain do not enforce controls promised in their documentation

Vulnerability summary

CVE-2018-5741 is a medium (CVSS 6.5) Incorrect Authorization vulnerability in isc bind. EPSS estimates a 3.45% chance of exploitation in the next 30 days, higher than 89% of scored vulnerabilities.

Timeline

1. 16-01-2019
   PublishedVulnerability first disclosed.
2. 17-09-2024
   Last modifiedVulnerability information updated.

Description

To provide fine-grained controls over the ability to use Dynamic DNS (DDNS) to update records in a zone, BIND 9 provides a feature called update-policy. Various rules can be configured to limit the types of updates that can be performed by a client, depending on the key used when sending the update request. Unfortunately, some rule types were not initially documented, and when documentation for them was added to the Administrator Reference Manual (ARM) in change #3112, the language that was added to the ARM at that time incorrectly described the behavior of two rule types, krb5-subdomain and ms-subdomain. This incorrect documentation could mislead operators into believing that policies they had configured were more restrictive than they actually were. This affects BIND versions prior to BIND 9.11.5 and BIND 9.12.3.

• CWE-863Incorrect AuthorizationThe product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.