unbound: Unbound: Denial of Service via crafted DNS responses with expired records

A flaw in Unbound allows a remote attacker controlling a delegated domain to trigger a NULL pointer dereference and crash the daemon. Exploitation occurs when serve-expired: yes and specific response-ip or RPZ rules are configured, resulting in a denial of service...

Directory Traversal

Overview Affected versions of this package are vulnerable to Directory Traversal in the ServeHTTP function in pkg/middlewares/replacepathregex/replacepathregex.go, which forwards the post-substitution path to the backend without checking whether it normalizes to a different route. An attacker can...

Directory Traversal

Overview Affected versions of this package are vulnerable to Directory Traversal in the ServeHTTP function in pkg/middlewares/replacepathregex/replacepathregex.go, which forwards the post-substitution path to the backend without checking whether it normalizes to a different route. An attacker can...

CVE-2026-56444 Degradation of resolution service when 'discard-timeout' and 'serve-expired-client-timeout' are combined in unusual configuration

In NLnet Labs Unbound 1.20.0 up to and including 1.25.1, when Unbound is configured with 'serve-expired: yes' and 'serve-expired-client-timeout discard-timeout 0' contrary to the suggested values, the discard-timeout branch during the serve expired logic drops an aged client reply without...

CVE-2026-56444

CVE-2026-56444 affects NLnet Labs Unbound 1.20.0 through 1.25.1. When configured with serve-expired: yes and serve-expired-client-timeout > discard-timeout > 0, the discard-timeout branch in the serve-expired logic fails to decrement the counter for aged client replies, unlike other branche...

EUVD-2026-47685

In NLnet Labs Unbound 1.20.0 up to and including 1.25.1, when Unbound is configured with 'serve-expired: yes' and 'serve-expired-client-timeout discard-timeout 0' contrary to the suggested values, the discard-timeout branch during the serve expired logic drops an aged client reply without...

CVE-2026-56444

In NLnet Labs Unbound 1.20.0 up to and including 1.25.1, when Unbound is configured with 'serve-expired: yes' and 'serve-expired-client-timeout discard-timeout 0' contrary to the suggested values, the discard-timeout branch during the serve expired logic drops an aged client reply without...

CVE-2026-56444 Degradation of resolution service when 'discard-timeout' and 'serve-expired-client-timeout' are combined in unusual configuration

In NLnet Labs Unbound 1.20.0 up to and including 1.25.1, when Unbound is configured with 'serve-expired: yes' and 'serve-expired-client-timeout discard-timeout 0' contrary to the suggested values, the discard-timeout branch during the serve expired logic drops an aged client reply without...

CVE-2026-56444

In NLnet Labs Unbound 1.20.0 up to and including 1.25.1, when Unbound is configured with 'serve-expired: yes' and 'serve-expired-client-timeout discard-timeout 0' contrary to the suggested values, the discard-timeout branch during the serve expired logic drops an aged client reply without...

CVE-2026-55717 'serve-expired-client-timeout' and 'response-ip' CNAME redirect could lead to a crash

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

CVE-2026-55717 'serve-expired-client-timeout' and 'response-ip' CNAME redirect could lead to a crash

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

CVE-2026-55717

Vulnerability CVE-2026-55717 affects NLnet Labs Unbound 1.10.0 through 1.25.1. When serve-expired is yes and a response-ip/ RPZ CNAME-based redirect is configured, a remote attacker controlling any delegated zone can crash the daemon. The serve-expired-client-timeout routine chase loop on the res...

CVE-2026-55717

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

CVE-2026-55717

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

CVE-2026-55717

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

EUVD-2026-47680

In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: redirect' /'response-ip-data: CNAME ' rule or the RPZ 'rpz-cname-override' equivalent, a remote client who controls any delegated domain can crash the daemon. The...

CVE-2026-46582 A wildcard replay, as another piece of data, triggers poisoning in the serve expired reply path

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...

CVE-2026-46582

Affected software/versions: NLnet Labs Unbound 1.6.0 up to and including 1.25.1. Issue: a replay of a wildcard RRset as another piece of data can be momentarily treated as DNSSEC secure based on RRSIG validation and cached, then misvalidated on the serve-expired path due to later NSEC validation,...

EUVD-2026-47670

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...

CVE-2026-46582 A wildcard replay, as another piece of data, triggers poisoning in the serve expired reply path

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...