CVE-2016-6170

Name: CVE-2016-6170
Creator: NVD / NIST
Published: 2016-07-06T14:59:05.597+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 40.54%

Last modified Jun 17, 2026

CVE-2016-6170 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. ISC BIND through 9.9.9-P1, 9.10.x through 9.10.4-P1, and 9.11.x through 9.11.0b1 allows primary DNS servers to cause a denial of service (secondary DNS server crash) via a large AXFR response, and possibly allows IXFR servers to cause a denial of service (IXFR client crash) via a large IXFR response and allows remote authenticated users to cause a denial of service (primary DNS server crash) via a large UPDATE message.. EPSS estimates a 40.54% chance of exploitation in the next 30 days.

Description

ISC BIND through 9.9.9-P1, 9.10.x through 9.10.4-P1, and 9.11.x through 9.11.0b1 allows primary DNS servers to cause a denial of service (secondary DNS server crash) via a large AXFR response, and possibly allows IXFR servers to cause a denial of service (IXFR client crash) via a large IXFR response and allows remote authenticated users to cause a denial of service (primary DNS server crash) via a large UPDATE message.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

40.54%

98.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions	Update
Isc	Bind	>= 9.0, <= 9.9.8	—
Isc	Bind	>= 9.10.0, <= 9.10.3	—
Isc	Bind	9.9.9	—
Isc	Bind	9.10.4	—
Isc	Bind	9.11.0	A1
Redhat	Enterprise Linux	5.0	—
Redhat	Enterprise Linux	6.0	—
Redhat	Enterprise Linux	7.0	—

References

http://www.openwall.com/lists/oss-security/2016/07/06/3Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/91611Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1036241Third Party Advisory, VDB Entry
https://bugzilla.redhat.com/show_bug.cgi?id=1353563Issue Tracking, Patch, Third Party Advisory
https://github.com/sischkg/xfer-limit/blob/master/README.mdExploit, Patch, Third Party Advisory
https://kb.isc.org/article/AA-01390Vendor Advisory
https://kb.isc.org/article/AA-01390/169/CVE-2016-6170Vendor Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015058.htmlMailing List, Third Party Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015073.htmlMailing List, Third Party Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015075.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201610-07Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/07/06/3Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/91611Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1036241Third Party Advisory, VDB Entry
https://bugzilla.redhat.com/show_bug.cgi?id=1353563Issue Tracking, Patch, Third Party Advisory
https://github.com/sischkg/xfer-limit/blob/master/README.mdExploit, Patch, Third Party Advisory
https://kb.isc.org/article/AA-01390Vendor Advisory
https://kb.isc.org/article/AA-01390/169/CVE-2016-6170Vendor Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015058.htmlMailing List, Third Party Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015073.htmlMailing List, Third Party Advisory
https://lists.dns-oarc.net/pipermail/dns-operations/2016-July/015075.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201610-07Third Party Advisory

Timeline

Published: Jul 6, 2016
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2016-6170?

How severe is CVE-2016-6170?

CVE-2016-6170 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 40.54% probability of exploitation in the next 30 days.

How do I fix CVE-2016-6170?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2016-6170?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST