{"id":"CVE-2018-5738","aliases":["ALPINE-CVE-2018-5738","BELL-CVE-2018-5738","DEBIAN-CVE-2018-5738","EUVD-2018-17507","GHSA-cg2m-4gq8-j388","UBUNTU-CVE-2018-5738","USN-3683-1"],"status":"published","title":"Some versions of BIND can improperly permit recursive query service to unauthorized clients","description":"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-\u003e9.12.1-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.","severity":{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.1137,"percentile":0.96018,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-200"],"published":"2018-06-12T00:00:00Z","modified":"2026-10-24T10:30:24Z","fixes":[{"ecosystem":"Alpine:v3.10","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.11","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.12","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.13","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.14","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.15","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.16","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.17","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.18","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.19","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.20","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.21","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.22","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.23","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.6","package":"bind","fixed_in":["9.11.5_p4-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.7","package":"bind","fixed_in":["9.11.5_p4-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.9","package":"bind","fixed_in":["9.12.2_p1-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"bind9","fixed_in":["1:9.11.3+dfsg-2"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"bind9","fixed_in":["1:9.11.3+dfsg-2"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"bind9","fixed_in":["1:9.11.3+dfsg-2"],"sources":["osv"]},{"ecosystem":"Ubuntu:18.04:LTS","package":"bind9","fixed_in":["1:9.11.3+dfsg-1ubuntu1.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.10","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.11","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.12","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.13","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.14","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.15","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.16","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.17","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.18","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.19","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.20","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.21","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.22","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.6","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.11.5_p4-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.7","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.11.5_p4-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.9","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.12.2_p1-r0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"bind9","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.11.3+dfsg-2"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"bind9","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.11.3+dfsg-2"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"bind9","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.11.3+dfsg-2"}]}]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"bind9","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.11.3+dfsg-1ubuntu1.1"}]}],"versions":["1:9.10.3.dfsg.P4-12.6ubuntu1","1:9.11.2.P1-1ubuntu2","1:9.11.2.P1-1ubuntu3","1:9.11.2.P1-1ubuntu4","1:9.11.2.P1-1ubuntu5","1:9.11.3+dfsg-1ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"bind9","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:9.11.3+dfsg-1ubuntu1.1"}]}],"versions":["1:9.10.3.dfsg.P4-12.6ubuntu1","1:9.11.2.P1-1ubuntu2","1:9.11.2.P1-1ubuntu3","1:9.11.2.P1-1ubuntu4","1:9.11.2.P1-1ubuntu5","1:9.11.3+dfsg-1ubuntu1"]}],"products":[{"vendor":"canonical","product":"ubuntu_linux"},{"vendor":"isc","product":"bind"},{"vendor":"isc","product":"bind 9"}],"references":[{"url":"https://usn.ubuntu.com/3683-1/","tags":["vendor-advisory","x_refsource_UBUNTU","x_transferred","Third Party Advisory","advisory"]},{"url":"https://kb.isc.org/docs/aa-01616","tags":["x_refsource_CONFIRM","x_transferred","Mitigation","Vendor Advisory","advisory"]},{"url":"http://www.securitytracker.com/id/1041115","tags":["vdb-entry","x_refsource_SECTRACK","x_transferred","Third Party Advisory","VDB Entry","advisory"]},{"url":"https://security.gentoo.org/glsa/201903-13","tags":["vendor-advisory","x_refsource_GENTOO","x_transferred","Third Party Advisory","advisory"]},{"url":"https://security.netapp.com/advisory/ntap-20190830-0002/","tags":["x_refsource_CONFIRM","x_transferred","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-5738"},{"url":"https://github.com/advisories/GHSA-cg2m-4gq8-j388"},{"url":"https://security.alpinelinux.org/vuln/CVE-2018-5738","tags":["advisory"]},{"url":"https://docs.bell-sw.com/security/cves/CVE-2018-5738","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2018-5738","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2018-5738","tags":["report"]},{"url":"https://kb.isc.org/article/AA-01616/0/CVE-2018-5738","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-3683-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2018-5738","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2018-5738","title":"Some versions of BIND can improperly permit recursive query service to unauthorized clients","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:00:00Z","modified":"2024-09-16T22:20:36.711Z","cvss":[{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"updated_at":"2026-11-02T14:35:00.948726Z"}],"euvd":[{"id":"EUVD-2018-17507","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:00:00Z","modified":"2024-09-16T22:20:36Z","cvss":[{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-03T00:55:03.975609Z"}],"ghsa":[{"id":"GHSA-cg2m-4gq8-j388","title":"Change #4777 (introduced in October 2017) introduced an unforeseen issue in releases which were...","description":"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-\u003e9.12.1-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.","status":"published","published":"2022-05-14T00:52:09Z","modified":"2023-02-02T05:02:36Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T14:51:28.758736Z"}],"nvd":[{"id":"CVE-2018-5738","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:29:00.907Z","modified":"2026-06-17T02:00:41.363Z","cvss":[{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"},{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T14:04:53.079938Z"}],"osv":[{"id":"ALPINE-CVE-2018-5738","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:29:00.907Z","modified":"2026-10-23T17:17:55.278642278Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:27:47.663013Z"},{"id":"BELL-CVE-2018-5738","title":"CVE-2018-5738 does not affect BellSoft software","status":"withdrawn","published":"2023-08-31T12:16:27.112416Z","modified":"2026-01-26T09:47:38.663303Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:28:14.701973Z"},{"id":"CVE-2018-5738","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:29:00.907Z","modified":"2026-10-24T10:30:24.816104299Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:09.442568Z"},{"id":"DEBIAN-CVE-2018-5738","description":"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-\u003e9.12.1-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.","status":"published","published":"2019-01-16T20:29:00.907Z","modified":"2026-10-23T18:03:58.423124885Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:30.867575Z"},{"id":"UBUNTU-CVE-2018-5738","description":"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-\u003e9.12.1-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.","status":"published","published":"2018-06-12T00:00:00Z","modified":"2026-04-22T11:59:39.008869Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:18.33562Z"},{"id":"USN-3683-1","title":"bind9 vulnerability","description":"Andrew Skalski discovered that Bind could incorrectly enable recursion\nwhen the \"allow-recursion\" setting wasn't specified. This issue could\nimproperly permit recursion to all clients, contrary to expectations.\n","status":"published","published":"2018-06-13T11:18:53Z","modified":"2026-04-22T09:46:19.151165Z","updated_at":"2026-11-02T16:58:13.496563Z"}]}}