CVE-2019-6465: Controls for zone transfers might not be properly applied to Dynamically Loadable Zones (DLZs) if the zones are writable.

[Michael McNally]

CVE:                 CVE-2019-6465
Document version:    2.0
Posting date:        21 February 2019
Program impacted:    BIND

Versions affected:   BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.5-P2,
                     9.12.0 -> 9.12.3-P2, and versions 9.9.3-S1 -> 9.11.5-S3
                     of BIND 9 Supported Preview Edition. Versions 9.13.0 ->
                     9.13.6 of the 9.13 development branch are also
affected.
                     Versions prior to BIND 9.9.0 have not been
evaluated for
                     vulnerability to CVE-2019-6465.

Severity:            Medium
Exploitable:         Remotely

Description:

   Controls for zone transfers may not be properly applied to
   Dynamically Loadable Zones (DLZs) if the zones are writable.

Impact:

   A client exercising this defect can request and receive a zone
   transfer of a DLZ even when not permitted to do so by the
   allow-transfer ACL.

CVSS Score:          5.3
CVSS Vector:         CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

For more information on the Common Vulnerability Scoring System and
to obtain your specific environmental score please visit:
https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Workarounds:         None
Active exploits:     None known.

Solution:

   Upgrade to the patched release most closely related to your
   current version of BIND:

   +  BIND 9.11.5-P4
   +  BIND 9.12.3-P4

   BIND Supported Preview Edition is a special feature preview
   branch of BIND provided to eligible ISC support customers.

   +  BIND 9.11.5-S5

Document revision history:

   1.0 Early Notification, 28 January 2019
   2.0 Public Disclosure, 21 February 2019

Related documents:

   See our BIND 9 Security Vulnerability Matrix for a complete
   listing of security vulnerabilities and versions affected.

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should go to security-officer at isc.org. To report a new issue, please
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issues at: 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/.)

ISC Security Vulnerability Disclosure Policy:

   Details of our current security advisory policy and practice can
   be found in the ISC Software Defect and Security Vulnerability
   Disclosure Policy.

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