cve-2026-5950-bind9-resolver-dos

CVE-2026-5950 - BIND 9 Resolver DoS Research notes and defensive guidance for CVE-2026-5950, an unbounded resend loop vulnerability in the BIND 9 resolver state machine. Overview CVE-2026-5950 affects recursive BIND 9 resolvers. Under specific retry and bad-server handling conditions, a remote...

BIND 9 Update Fixes 14 Flaws, Including an Unauthenticated Crash Over DNS-over-HTTPS

The Internet Systems Consortium ISC has released BIND 9.20.29 and 9.21.26 to fix fourteen security flaws it disclosed on 16 September in BIND 9, its open-source DNS server software. One of them affects any BIND server that answers DNS-over-HTTPS DoH. A sender with no credentials can crash the...

BIND-9-Cache-Poisoning-PoC---CVE-2025-40778

BIND 9 Cache Poisoning PoC - CVE-2025-40778 Conceptual Overview This vulnerability allows an attacker to corrupt the DNS cache of a BIND Resolver, forcing legitimate users to be redirected to malicious IP addresses without their knowledge. The core logic of the attack: The attack relies on...

CVE-2026-19941

A flaw was found in BIND 9. A remote attacker could exploit this by providing an inapplicable NSEC Next Secure record to a named resolver. This could allow the attacker to mask the existence of a victim's wildcard DNS Domain Name System record, potentially leading to a misrepresentation of DNS...

CVE-2026-77119

A flaw was found in BIND 9. A remote attacker could exploit a vulnerability where a validly signed NSEC3 record from an unrelated DNS zone might be accepted as proof of insecurity. This could downgrade a secure delegation, allowing forged unsigned DNS answers to be accepted by the resolver,...

CVE-2026-19662

A flaw was found in BIND 9. A remote attacker can cause a named resolver to stop functioning Denial of Service by inducing the victim resolver to send multiple queries for a DNSSEC-signed zone. If the attacker's authoritative server responds with a specific sequence of crafted answers that arrive...

DEBIAN-CVE-2026-77119

A validly signed NSEC3 from an unrelated sibling zone may be accepted as an insecurity proof, downgrading a secure delegation and letting a forged unsigned answer through. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through...

CVE-2026-77119

A validly signed NSEC3 from an unrelated sibling zone may be accepted as an insecurity proof, downgrading a secure delegation and letting a forged unsigned answer through. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through...

DEBIAN-CVE-2026-75029

In a query response, an attacker may send named multiple copies of a record that should only exist once such as an SOA record. If the RDATA is the same on all the copies, the record is appended to the in-memory RDATA set, which can cause increased memory usage of the negative cache and possibly...

DEBIAN-CVE-2026-76163

If BIND is loaded with a "named.conf" file that contains no global "options" block, an attacker can send a query of QTYPE TKEY which may cause an assertion failure and subsequent unexpected program exit. This issue affects BIND 9 versions 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, and...

CVE-2026-75029

In a query response, an attacker may send named multiple copies of a record that should only exist once such as an SOA record. If the RDATA is the same on all the copies, the record is appended to the in-memory RDATA set, which can cause increased memory usage of the negative cache and possibly...

CVE-2026-76163

If BIND is loaded with a "named.conf" file that contains no global "options" block, an attacker can send a query of QTYPE TKEY which may cause an assertion failure and subsequent unexpected program exit. This issue affects BIND 9 versions 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, and...

CVE-2026-19033

For a secondary zone with transfers restricted by TSIG, named may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to ...

DEBIAN-CVE-2026-19666

On a resolver configured to use dns64, if an applicable answer from the authoritative server is malformed in a specific way, the resolver named process will exit unexpectedly. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1...

AZL-103119 CVE-2026-19033 affecting package bind 9.20.26-1

For a secondary zone with transfers restricted by TSIG, named may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to ...

DEBIAN-CVE-2026-19033

For a secondary zone with transfers restricted by TSIG, named may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to ...

CVE-2026-19668

A BIND recursive resolver may experience excessive resource consumption if it encounters large numbers of a particular kind of invalid DNSSEC record. Default limits on "max-records-per-type" and "max-types-per-name" help mitigate the exposure. This issue affects BIND 9 versions 9.11.0 through...

CVE-2026-19666

On a resolver configured to use dns64, if an applicable answer from the authoritative server is malformed in a specific way, the resolver named process will exit unexpectedly. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1...

CVE-2026-75029

A flaw was found in BIND 9. A remote attacker could send multiple copies of a single record in a query response to the named service. This could lead to increased memory usage in the negative cache, potentially causing a Denial of Service DoS due to memory exhaustion. Mitigation To mitigate this...

CVE-2026-81736

A flaw was found in BIND 9. A remote attacker can exploit this vulnerability by querying a BIND resolver for the root of a specially crafted, cached tree of SVCB/HTTPS AliasMode records. This action causes the resolver to spend a disproportionate amount of CPU time constructing the response,...