CVE-2019-6471: A race condition when discarding malformed packets can cause BIND to exit with an assertion failure
Document version: 2.0
Posting date: 19 June 2019
Program impacted: BIND
Versions affected: BIND 9.11.0 -> 9.11.7, 9.12.0 -> 9.12.4-P1, 9.14.0 -> 9.14.2. Also all releases of the BIND 9.13 development branch and version 9.15.0 of the BIND 9.15 development branch. BIND Supported Preview Edition versions 9.11.3-S1 -> 9.11.7-S1.
A race condition which may occur when discarding malformed packets can result in BIND exiting due to a REQUIRE assertion failure in dispatch.c.
An attacker who can cause a resolver to perform queries which will be answered by a server which responds with deliberately malformed answers can cause named to exit, denying service to clients.
CVSS Score: 5.9
CVSS Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
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:H/PR:N/UI:N/S:U/C:N/I:N/A:H.
Upgrade to the patched release most closely related to your current version of BIND:
- BIND 9.11.8
- BIND 9.12.4-P2
- BIND 9.14.3
- BIND 9.15.1
BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.
- BIND 9.11.8-S1
Acknowledgements: ISC would like to thank CERN for helping us to discover this issue.
Document revision history:
1.0 Early Notification, 12 June 2019
2.0 Public Disclosure, 19 June 2019
See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.
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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/.)
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