CVE-2026-56416

In NLnet Labs Unbound up to and including version 1.25.1, when the validator builds the canonical RDATA form for an RRSIG-covered PX/RP/MINFO/SOA RRset, it computes the address of the second embedded domain name as 'datstart + dnamevaliddatstart, ...' and passes it straight to 'querydnametolower'...

EUVD-2026-47684

In NLnet Labs Unbound up to and including version 1.25.1, when the validator builds the canonical RDATA form for an RRSIG-covered PX/RP/MINFO/SOA RRset, it computes the address of the second embedded domain name as 'datstart + dnamevaliddatstart, ...' and passes it straight to 'querydnametolower'...

CVE-2026-56416 Possible heap buffer overflow when validator canonicalizes RDATA that contains domain name

In NLnet Labs Unbound up to and including version 1.25.1, when the validator builds the canonical RDATA form for an RRSIG-covered PX/RP/MINFO/SOA RRset, it computes the address of the second embedded domain name as 'datstart + dnamevaliddatstart, ...' and passes it straight to 'querydnametolower'...

CVE-2026-55973

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

CVE-2026-55973

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

CVE-2026-55708 Privacy/configuration issue when adding local data in views through 'unbound-control'

In NLnet Labs Unbound 1.6.0 up to and including 1.25.1, the 'viewlocaldata' and 'viewlocaldatas' commands of 'unbound-control' create a bare local zones tree for an already configured named view when the view is configured with no local data to begin with. However, the creation through the contro...

CVE-2026-55708

In NLnet Labs Unbound 1.6.0 up to and including 1.25.1, the 'viewlocaldata' and 'viewlocaldatas' commands of 'unbound-control' create a bare local zones tree for an already configured named view when the view is configured with no local data to begin with. However, the creation through the contro...

CVE-2026-54478

In NLnet Labs Unbound 1.18.0 up to and including 1.25.1, when Unbound listens on a 'proxy-protocol-port' interface with 'answer-cookie: yes', the RFC 9018 server-cookie SipHash is computed over the proxy's wire address instead of the PROXYv2-declared client. One server cookie obtained through a...

CVE-2026-54478

CVE-2026-54478 affects NLnet Labs Unbound 1.18.0–1.25.1 when listening on a proxy-protocol-port with answer-cookie enabled. The RFC 9018 server-cookie (SipHash) is computed over the proxy’s wire address rather than the PROXYv2-declared client, causing a server cookie to validate for every PROXYv2...

EUVD-2026-47677

In NLnet Labs Unbound 1.25.0 up to and including 1.25.1, a fix that makes the 'respip' and 'dns64' modules work together, creates a shallow copy of the view name in effect that could lead to memory corruption if the owner of the original view name is jostled out when Unbound is under pressure...

CVE-2026-52863

The CVE concerns NLnet Labs Unbound 1.25.0–1.25.1. A fix that enables coexistence of the respip and dns64 modules creates a shallow copy of the view name, which, under pressure when a configured access-control-view is active and subqueries (respip CNAME redirection, dns64, subnetcache) are attach...

CVE-2026-52863 Memory corruption could lead to crash and denial of service

In NLnet Labs Unbound 1.25.0 up to and including 1.25.1, a fix that makes the 'respip' and 'dns64' modules work together, creates a shallow copy of the view name in effect that could lead to memory corruption if the owner of the original view name is jostled out when Unbound is under pressure...

CVE-2026-50252 Possible cache poisoning attack by mapping source port population per thread

In NLnet Labs Unbound 1.4.22 up to and including 1.25.1, UDP source port is randomized and intended to serve as a secret value that increases the entropy of DNS transactions. When resolver load balancing policies depend on the source port while their outcome is revealed this secrecy is undermined...

CVE-2026-50248

In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, when an auth/rpz zone has a configured primary hostname that resolves to BOGUS A/AAAA, it is still considered as a possible XFR endpoint. A malicious actor that can spoof the hostname's A/AAAA record no valid RRSIG required becomes the zone'...

EUVD-2026-47673

In NLnet Labs Unbound 1.6.2 up to and including 1.25.1, when Unbound is configured with the 'respip' module in front of the validator together with a 'response-ip' redirect rule or an RPZ file with an RPZ-IP trigger, the rewriting handler does not check the security status of the upstream answer...

CVE-2026-50046

In NLnet Labs Unbound 1.15.0 up to and including 1.25.1, the TLS server name used for DNS-over-TLS DoT forwarded queries is tied to a struct's 'servicedquery' lifetime but also referenced by another struct 'waitingtcp'. When the owning struct is jostled out of the mesh while the DoT TCP stream is...

CVE-2026-50046

In NLnet Labs Unbound 1.15.0 up to and including 1.25.1, the TLS server name used for DNS-over-TLS DoT forwarded queries is tied to a struct's 'servicedquery' lifetime but also referenced by another struct 'waitingtcp'. When the owning struct is jostled out of the mesh while the DoT TCP stream is...

CVE-2026-50045

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a single client query for a deeply nested name under a DNSSEC-signed parent can cause Unbound to send more upstream packets per client query than the configured 'max-global-quota'. This effectively bypasses a security configuration that...

CVE-2026-50045

CVE-2026-50045 affects NLnet Labs Unbound, versions 1.22.0 through 1.25.1. A single client query for a deeply nested name under a DNSSEC-signed parent can cause Unbound to exceed the configured ‘max-global-quota’, effectively bypassing the upstream-traffic amplification limiter. The vulnerability...

CVE-2026-46582

In NLnet Labs Unbound 1.6.0 up to and including 1.25.1, a replay of a wildcard rrset as another piece of data, could be briefly considered DNSSEC secure based only on the RRSIG validation and stored into cache, before later validation treats it as bogus based on NSEC validation. When the resolvin...