Amazon Linux 2 : unbound, --advisory ALAS2UNBOUND-1.17-2026-009 (ALASUNBOUND-1.17-2026-009)

The version of unbound installed on the remote host is prior to 1.17.0-2. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2UNBOUND-1.17-2026-009 advisory. In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, insufficient validation of the RRSIG.Labels field...

CVE-2026-50251

A flaw was found in Unbound. A remote malicious actor can exploit a vulnerability by controlling a DNS delegation that returns specific glue records. This can cause Unbound to repeatedly clear its DNS caches, leading to a continuous Denial of Service DoS for DNS resolution. Mitigation To mitigate...

SUSE CVE-2026-42955

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other...

SUSE CVE-2026-50251

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

Linux Distros Unpatched Vulnerability : CVE-2026-42955

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found ...

Linux Distros Unpatched Vulnerability : CVE-2026-50251

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of...

Extra fix for CVE-2026-40622 to also clamp the TTL of A/AAAA records disallowing a one-time 'ghost domain' delegation renewal via glue records

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CVE-2026-50251

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-50251

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-42955

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other...

unbound: NLnet Labs Unbound: Denial of Service via crafted DNS glue records

A flaw was found in Unbound. A remote malicious actor can exploit a vulnerability by controlling a DNS delegation that returns specific glue records. This can cause Unbound to repeatedly clear its DNS caches, leading to a continuous Denial of Service DoS for DNS resolution...

CVE-2026-50251 Attacker supplied '0.0.0.0'/'::' glue triggers defensive full-cache flush

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

EUVD-2026-47675

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-50251

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-50251 Attacker supplied '0.0.0.0'/'::' glue triggers defensive full-cache flush

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-50251

In NLnet Labs Unbound up to and including version 1.25.1, when 'unwanted-reply-threshold' is enabled set to any value greater than zero, glue records of 0.0.0.0/::0 can short-circuit Unbound, on systems that can direct such traffic, by issuing DNS queries and receiving seemingly unwanted replies...

CVE-2026-42955

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other...

CVE-2026-42955

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other...

CVE-2026-42955

NLnet Labs Unbound versions 1.16.2–1.25.1 are affected by CVE-2026-42955, a variant of CVE-2026-40622. An adversary controlling a ghost zone and able to query Unbound can cause the cache to overwrite expired parent-side glue A/AAAA records, extending the ghost domain window by up to one cached TT...

CVE-2026-42955 Extra fix for CVE-2026-40622 to also clamp the TTL of A/AAAA records disallowing a one-time 'ghost domain' delegation renewal via glue records

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other...