unbound: Unbound: Cache poisoning via insufficient RRSIG.Labels validation and premature cache writes

A flaw was found in Unbound. Insufficient validation of the RRSIG.Labels field, combined with premature cache writes during RFC 8198 aggressive NSEC processing, can lead to cache poisoning. This vulnerability allows a malicious actor, controlling a single delegated zone, to poison arbitrary sibli...

CVE-2026-12617

CVE-2026-12617 affects ISC BIND 9: vulnerable in 9.18.0–9.18.50 and 9.20.0–9.20.24 (including 9.18.11-S1–9.18.50-S1 and 9.20.9-S1–9.20.24-S1). The issue causes named to quit unexpectedly when handling responses for CNAME/DNAME and A records under certain query/order scenarios, potentially leading...

CVE-2026-12617

The issue is unexpected program termination based on ordering and/or specific content in responses to queries for CNAME or DNAME, and A records. Specifically, if a client queries for a DNAME and A record below the DNAME to the resolver, and the authoritative server responds positively to the A...

EUVD-2026-47711

The issue is unexpected program termination based on ordering and/or specific content in responses to queries for CNAME or DNAME, and A records. Specifically, if a client queries for a DNAME and A record below the DNAME to the resolver, and the authoritative server responds positively to the A...

CVE-2026-12617

The issue is unexpected program termination based on ordering and/or specific content in responses to queries for CNAME or DNAME, and A records. Specifically, if a client queries for a DNAME and A record below the DNAME to the resolver, and the authoritative server responds positively to the A...

EUVD-2026-47709

It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes named to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For...

CVE-2026-11605

The issue is a resource exhaustion vulnerability associated with DNSSEC validation. BIND always validates all RRSIG records in an answer, even if they are not strictly needed. A query to an authoritative server/zone which returns many valid but superfluous RRSIG records causes the validator to...

CVE-2026-11605

The issue is a resource exhaustion vulnerability associated with DNSSEC validation. BIND always validates all RRSIG records in an answer, even if they are not strictly needed. A query to an authoritative server/zone which returns many valid but superfluous RRSIG records causes the validator to...

EUVD-2026-47706

An attacker who knows or guesses that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of...

CVE-2026-10822

If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit. BIND will first need to store a DNS record for a key KEY, DNSKEY, etc.. That key must specify a PRIVATEDNS algorithm 253, and in the algorithm identifier,...

CVE-2026-10822

If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit. BIND will first need to store a DNS record for a key KEY, DNSKEY, etc.. That key must specify a PRIVATEDNS algorithm 253, and in the algorithm identifier,...

CVE-2026-10822

CVE-2026-10822 (BIND) : The issue affects BIND 9 across multiple branches (9.18.0–9.18.50, 9.20.0–9.20.24, 9.21.0–9.21.23, plus -S1 variants). It arises when storing a DNSKEY/KEY with a PRIVATEDNS algorithm (253) where the algorithm identifier has an incorrect length, causing an invalid identifie...

CVE-2026-10822 Key Record using PRIVATEDNS algorithm may lead to unexpected exit

If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit. BIND will first need to store a DNS record for a key KEY, DNSKEY, etc.. That key must specify a PRIVATEDNS algorithm 253, and in the algorithm identifier,...

CVE-2026-55991

CVE-2026-55991 affects NLnet Labs Unbound 1.22.0–1.25.1. A remote unauthenticated DoQ client can trigger a libngtcp2 assertion by passing an erroneous error value when ngtcp2_conn_writev_stream() returns NGTCP2_ERR_STREAM_DATA_BLOCKED and Unbound calls ngtcp2_ccerr_set_application_error() with -1...

CVE-2026-55991

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a remote unauthenticated client can trigger a libngtcp2 assertion if compiled with assertions on and terminate the entire Unbound process using a single DNS-over-QUIC DoQ connection and one normal DNS query. This is caused by an erroneous...

EUVD-2026-47683

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a remote unauthenticated client can trigger a libngtcp2 assertion if compiled with assertions on and terminate the entire Unbound process using a single DNS-over-QUIC DoQ connection and one normal DNS query. This is caused by an erroneous...

CVE-2026-55991

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a remote unauthenticated client can trigger a libngtcp2 assertion if compiled with assertions on and terminate the entire Unbound process using a single DNS-over-QUIC DoQ connection and one normal DNS query. This is caused by an erroneous...

CVE-2026-55973

CVE-2026-55973 affects NLnet Labs Unbound 1.23.0 through 1.25.1. When dns-error-reporting: yes is enabled, the EDNS Report-Channel option (code 18) length from the last upstream response is treated as the length of the agent domain. If the agent domain contains garbage after the domain, those byt...

CVE-2026-55973 'dns-error-reporting: yes' leads to stack buffer overflow

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 'dns-error-reporting: yes' leads to stack buffer overflow

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...