CVE-2019-16866

Description

Unbound before 1.9.4 accesses uninitialized memory, which allows remote attackers to trigger a crash via a crafted NOTIFY query. The source IP address of the query must match an access-control rule.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.25% Top 25%
Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory nlnetlabs.nl
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/NLnetLabs/unbound/blob/release-1.9.4/doc/Changelog release notes product
https://nlnetlabs.nl/downloads/unbound/CVE-2019-16866.txt patch vendor advisory
https://usn.ubuntu.com/4149-1/ third party advisory vendor advisory
https://www.debian.org/security/2019/dsa-4544 vendor advisory
https://seclists.org/bugtraq/2019/Oct/23 mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/E65NCWZZB2D75ZIYWPXKMVGSGNYW4JMC/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MLRHE7TQFAOV4MB2ELTOGESZYUL65NUJ/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-16866?
CVE-2019-16866 has been scored as a high severity vulnerability.
How to fix CVE-2019-16866?
To fix CVE-2019-16866, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-16866 being actively exploited in the wild?
It is possible that CVE-2019-16866 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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