CVE-2026-81642

NLnet Labs Unbound (up to and including 1.26.0 ) contains a heap buffer overflow in the DNSSEC validator when digesting DNSKEY records. A DNSKEY with an owner compression pointer referencing its own RDATA can overflow the digest buffer, enabling denial of service and possible remote code executio...

CVE-2026-81642

In NLnet Labs Unbound up to and including 1.26.0, a vulnerability was found in the DNSSEC validator that enables denial of service and possible remote code execution as a result of digesting DNSKEYs. A DNSKEY with an owner compression pointer to its own RDATA can overflow the digest buffer. Remot...

CVE-2026-81642

In NLnet Labs Unbound up to and including 1.26.0, a vulnerability was found in the DNSSEC validator that enables denial of service and possible remote code execution as a result of digesting DNSKEYs. A DNSKEY with an owner compression pointer to its own RDATA can overflow the digest buffer. Remot...

CVE-2026-81634

NLnet Labs Unbound up to and including 1.26.0 is affected by a heap buffer overflow in the RRSet canonicalisation routine. The root cause is a missing first owner name in the buffer length check, which can be triggered by a 255-length query name combined with a large TCP response. Since canonical...

CVE-2026-81634 Possible heap buffer overflow during DNSSEC canonicalization

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a...

EUVD-2026-80290

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a...

CVE-2026-81634 Possible heap buffer overflow during DNSSEC canonicalization

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a...

CVE-2026-81634

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a...

CVE-2026-81634

In NLnet Labs Unbound up to and including 1.26.0, a 255 length query name with a large TCP response can lead to a heap buffer overflow during the RRSet canonicalisation routine. This is caused by missing to add the first owner name into the buffer length check. A malicious actor operating a...

EUVD-2026-80288

NLnet Labs Unbound 1.22.0 up to and including 1.26.1, has a use-after-free vulnerability when compiled for DNS-over-QUIC support with '--with-libngtcp2'. Each DoQ stream owns an output buffer that holds the DNS response. ngtcp2's retransmission buffer keeps a shallow pointer into the output buffe...

CVE-2026-78227 Use-after-free in DoQ stream output buffer on reset re-transmission

NLnet Labs Unbound 1.22.0 up to and including 1.26.1, has a use-after-free vulnerability when compiled for DNS-over-QUIC support with '--with-libngtcp2'. Each DoQ stream owns an output buffer that holds the DNS response. ngtcp2's retransmission buffer keeps a shallow pointer into the output buffe...

CVE-2026-78227

NLnet Labs Unbound versions 1.22.0 through 1.26.1 contain a use-after-free vulnerability in the DNS-over-QUIC (DoQ) implementation, triggered only when compiled with '--with-libngtcp2'. The root cause is that ngtcp2's retransmission buffer retains a shallow pointer into a per-stream output buffer...

CVE-2026-78227

NLnet Labs Unbound 1.22.0 up to and including 1.26.1, has a use-after-free vulnerability when compiled for DNS-over-QUIC support with '--with-libngtcp2'. Each DoQ stream owns an output buffer that holds the DNS response. ngtcp2's retransmission buffer keeps a shallow pointer into the output buffe...

EUVD-2026-80287

In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones zonemd-check: yes which are located below but not at a trust anchor allow for an attack window where tampered with zone contents are served or stored to disk prior to the ZONEMD integrity check. Th...

CVE-2026-77955 Possible ZONEMD verification bypass window

In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones zonemd-check: yes which are located below but not at a trust anchor allow for an attack window where tampered with zone contents are served or stored to disk prior to the ZONEMD integrity check. Th...

CVE-2026-77955

NLnet Labs Unbound versions 1.13.2 through 1.26.1 are affected by a timing window in ZONEMD verification for zones configured with zonemd-check: yes located below (but not at) a trust anchor. The root cause is the asynchronous DS/DNSKEY resolution required before the ZONEMD integrity check comple...

CVE-2026-77955 Possible ZONEMD verification bypass window

In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones zonemd-check: yes which are located below but not at a trust anchor allow for an attack window where tampered with zone contents are served or stored to disk prior to the ZONEMD integrity check. Th...

CVE-2026-77955

In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones zonemd-check: yes which are located below but not at a trust anchor allow for an attack window where tampered with zone contents are served or stored to disk prior to the ZONEMD integrity check. Th...

CVE-2026-77955

In NLnet Labs Unbound 1.13.2 up to and including 1.26.1, a vulnerability in ZONEMD configured zones zonemd-check: yes which are located below but not at a trust anchor allow for an attack window where tampered with zone contents are served or stored to disk prior to the ZONEMD integrity check. Th...

PT-2026-93372

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions prior to 1.27.0 Description A heap buffer overflow can occur during the RRSet canonicalisation routine when processing a 255 length query name with a large TCP response. This issue stems from a failure to include th...