VulnerabilityModified

CVE-2022-30698

NLnet Labs Unbound, up to and including version 1.16.1 is vulnerable to a novel type of the "ghost domain names" attack.

MEDIUM 6.5EPSS 1.05%

Does this matter?

Lower severity and a low EPSS score (1.05%). Track it; it rarely justifies an emergency change on its own.

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 subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. From version 1.16.2 on, Unbound checks the validity of parent delegation records before using cached delegation information.

CVSS 3.1: 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS: 1.05% probability · 62th percentile
CISA KEV: Not listed
Weakness: CWE-613
Affected: nlnetlabs/unbound · fedoraproject/fedora
Source: sep@nlnetlabs.nl

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.