CVE-2016-6171

HIGH 8.6CVE-2016-6171 · Published 09/02/2017 · updated 17/06/2026

In short

CVE-2016-6171 is a HIGH (CVSS 8.6) vulnerability affecting knot dns (knot-dns).
Chance of exploitation in the next 30 days (EPSS): 2.8%, higher than 86.5% of all vulnerabilities.
Fix: update to 2.3.0 or later.

Package	Affected versions	Patched versions
knot dns knot-dns	`< 2.3.0`	`2.3.0`

Description

Knot DNS before 2.3.0 allows remote DNS servers to cause a denial of service (memory exhaustion and slave server crash) via a large zone transfer for (1) DDNS, (2) AXFR, or (3) IXFR.

References

openwall.com/lists/oss-security/2016/07/06/3 · Mailing List
openwall.com/lists/oss-security/2016/07/06/4 · Mailing List
securityfocus.com/bid/91678 · Third Party Advisory
sischkg/xfer-limit · Patch
gitlab.labs.nic.cz/labs/knot/blob/c546a70563ef4c7badb7cb5bdf6d1ba8e7adae82/NEWS · Release Notes
gitlab.labs.nic.cz/labs/knot/issues/464 · Vendor Advisory
lists.dns-oarc.net/pipermail/dns-operations/2016-July/015058.html · Technical Description

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