CVE-2018-5738

Impact:
Moderate
Public Date:
2018-06-12
CWE:
CWE-284
Bugzilla:
1589616: CVE-2018-5738 bind: Improper handling of configuration allows all clients to perform recursive queries

The MITRE CVE dictionary describes this issue as:

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.

Find out more about CVE-2018-5738 from the MITRE CVE dictionary dictionary and NIST NVD.

CVSS v3 metrics

NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.

CVSS3 Base Score 5.3
CVSS3 Base Metrics CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity Impact None
Availability Impact None

Affected Packages State

Platform Package State
Red Hat Enterprise Linux 8 bind Not affected
Red Hat Enterprise Linux 7 bind Not affected
Red Hat Enterprise Linux 6 bind Not affected
Red Hat Enterprise Linux 5 bind97 Not affected
Red Hat Enterprise Linux 5 bind Not affected

Acknowledgements

Red Hat would like to thank ISC for reporting this issue.

External References

Last Modified

CVE description copyright © 2017, The MITRE Corporation