Change #4777 (introduced in October 2017) introduced an unforeseen issue in releases which were issued after that date, affecting which clients are permitted to make recursive queries to a BIND nameserver. The intended (and documented) behavior is that if an operator has not specified a value for the "allow-recursion" setting, it SHOULD default to one of the following: none, if "recursion no;" is set in named.conf; a value inherited from the "allow-query-cache" or "allow-query" settings IF "recursion yes;" (the default for that setting) AND match lists are explicitly set for "allow-query-cache" or "allow-query" (see the BIND9 Administrative Reference Manual section 6.2 for more details); or the intended default of "allow-recursion {localhost; localnets;};" if "recursion yes;" is in effect and no values are explicitly set for "allow-query-cache" or "allow-query". However, because of the regression introduced by change #4777, it is possible when "recursion yes;" is in effect and no match list values are provided for "allow-query-cache" or "allow-query" for the setting of "allow-recursion" to inherit a setting of all hosts from the "allow-query" setting default, improperly permitting recursion to all clients. Affects BIND 9.9.12, 9.10.7, 9.11.3, 9.12.0->9.12.1-P2, the development release 9.13.0, and also releases 9.9.12-S1, 9.10.7-S1, 9.11.3-S1, and 9.11.3-S2 from BIND 9 Supported Preview Edition.
NVD Severity
Other trackers
Mailing lists
GitHub (code, issues), Aports (code, issues)


Type URI
Third Party Advisory
Third Party Advisory
Third Party Advisory

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:isc:bind:9.12.0:*:*:*:*:*:*:* bind == None == 9.12.0
cpe:2.3:a:isc:bind:9.11.3:s2:*:*:*:*:*:* bind == None == 9.11.3
cpe:2.3:a:isc:bind:9.9.12:*:*:*:*:*:*:* bind == None == 9.9.12
cpe:2.3:a:isc:bind:9.12.1:*:*:*:*:*:*:* bind == None == 9.12.1
cpe:2.3:a:isc:bind:9.13.0:*:*:*:*:*:*:* bind == None == 9.13.0
cpe:2.3:a:isc:bind:9.10.7:*:*:*:*:*:*:* bind == None == 9.10.7

Vulnerable and fixed packages

Source package Branch Version Maintainer Status