CVE-2022-30699

Novel "ghost domain names" attack by updating almost expired delegation information

Description

NLnet Labs Unbound, up to and including version 1.16.1, is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a rogue domain name when the cached delegation information is about to expire. The rogue nameserver delays the response so that the cached delegation information is expired. Upon receiving the delayed answer containing the delegation information, Unbound overwrites the now expired entries. This action can be repeated when the delegation information is about to expire making the rogue delegation information ever-updating. From version 1.16.2 on, Unbound stores the start time for a query and uses that to decide if the cached delegation information can be overwritten.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory nlnetlabs.nl
Affected: NLnet Labs Unbound
Published at:
Updated at:

References

Link Tags
https://www.nlnetlabs.nl/downloads/unbound/CVE-2022-30698_CVE-2022-30699.txt vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5L3ZFWZZFPBIL654BG75RWXUMPFQJ5EC/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D35CX4SCZVNKZTWJXPDFTHWZHINMGEZD/ vendor advisory
https://security.gentoo.org/glsa/202212-02 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2023/03/msg00024.html mailing list

Frequently Asked Questions

What is the severity of CVE-2022-30699?
CVE-2022-30699 has been scored as a medium severity vulnerability.
How to fix CVE-2022-30699?
To fix CVE-2022-30699, 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-2022-30699 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-30699 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-30699?
CVE-2022-30699 affects NLnet Labs Unbound.
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