CVE-2025-8677

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols and provides an openly redistributable reference implementation of the major components of the Domain Name System. This package includes the components to operate a DNS server.

Security Fix(es):

Under certain circumstances, BIND is too lenient when accepting records from answers, allowing an attacker to inject forged data into the cache. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40778)

In specific circumstances, due to a weakness in the Pseudo Random Number Generator (PRNG) that is used, it is possible for an attacker to predict the source port and query ID that BIND will use. This issue affects BIND 9 versions 9.16.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.16.8-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40780)

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-8677)

Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols and provides an openly redistributable reference implementation of the major components of the Domain Name System. This package includes the components to operate a DNS server.

Security Fix(es):

Under certain circumstances, BIND is too lenient when accepting records from answers, allowing an attacker to inject forged data into the cache. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40778)

In specific circumstances, due to a weakness in the Pseudo Random Number Generator (PRNG) that is used, it is possible for an attacker to predict the source port and query ID that BIND will use. This issue affects BIND 9 versions 9.16.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.16.8-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40780)

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-8677)

Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols and provides an openly redistributable reference implementation of the major components of the Domain Name System. This package includes the components to operate a DNS server.

Security Fix(es):

Under certain circumstances, BIND is too lenient when accepting records from answers, allowing an attacker to inject forged data into the cache. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40778)

In specific circumstances, due to a weakness in the Pseudo Random Number Generator (PRNG) that is used, it is possible for an attacker to predict the source port and query ID that BIND will use. This issue affects BIND 9 versions 9.16.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.16.8-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-40780)

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.(CVE-2025-8677)

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)

• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)

• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

BIND (Berkeley Internet Name Domain) is an implementation of the DNS (Domain Name System) protocols. BIND includes a DNS server (named), which resolves host names to IP addresses; a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating properly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)

• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)

• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 9 Release Notes linked from the References section.

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)
• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)
• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

BIND (Berkeley Internet Name Domain) is an implementation of the DNS (Domain Name System) protocols. BIND includes a DNS server (named), which resolves host names to IP addresses; a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating properly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)
• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)
• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)
• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)
• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

BIND (Berkeley Internet Name Domain) is an implementation of the DNS (Domain Name System) protocols. BIND includes a DNS server (named), which resolves host names to IP addresses; a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating properly.

Security Fix(es):

• bind: Cache poisoning attacks with unsolicited RRs (CVE-2025-40778)
• bind: Cache poisoning due to weak PRNG (CVE-2025-40780)
• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The Berkeley Internet Name Domain (BIND) is an implementation of the Domain Name System (DNS) protocols. BIND includes a DNS server (named); a resolver library (routines for applications to use when interfacing with DNS); and tools for verifying that the DNS server is operating correctly.

Security Fix(es):

• bind: Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinuxRelease Notes linked from the References section.

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

Querying for records within a specially crafted zone containing certain malformed DNSKEY records can lead to CPU exhaustion. This issue affects BIND 9 versions 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

• CVE-2025-8677: fail DNSSEC validation on a matching but cryptographically invalid DNSKEY instead of skipping it, preventing CPU exhaustion from malformed DNSKEY records in a specially crafted zone

• CVE-2025-8677: fail DNSSEC validation on a matching but cryptographically invalid DNSKEY instead of skipping it, preventing CPU exhaustion from malformed DNSKEY records in a specially crafted zone

• SECURITY UPDATE: cache poisoning via unsolicited answer records
  • debian/patches/CVE-2025-40778.patch: require the NS RRset owner name to be an ancestor of the queried name, restrict cached glue to the NS bailiwick apex, and retry unsigned DNAME responses over TCP
  • CVE-2025-40778
• SECURITY UPDATE: excessive NSEC3 iterations CPU denial of service during insecure delegation validation
  • debian/patches/CVE-2026-1519.patch: cap NSEC3 iterations at DNS_NSEC3_MAXITERATIONS (150) in isdelegation() and skip already-trusted rdatasets during the insecurity proof
  • CVE-2026-1519

• SECURITY UPDATE: CPU exhaustion via malformed DNSKEY records
  • debian/patches/CVE-2025-8677.patch: fail validation on invalid DNSKEY in lib/dns/validator.c.
  • CVE-2025-8677
• SECURITY UPDATE: cache poisoning through forged records in answers
  • debian/patches/CVE-2025-40778.patch: tighten resolver caching rules in lib/dns/resolver.c and lib/dns/message.c, and raise the default max-recursion-queries from 32 to 50 in bin/named/config.c.
  • CVE-2025-40778
• SECURITY UPDATE: assertion failure on malformed PRIVATEDNS DNSKEY records
  • debian/patches/CVE-2026-10822.patch: make dns_name_fromwire() honour the active region of the source buffer in lib/dns/name.c.
  • CVE-2026-10822
• SECURITY UPDATE: crash from malformed NSEC/NSEC3 response
  • debian/patches/CVE-2026-13204.patch: treat a missing NOQNAME proof as an error instead of an assertion failure in lib/dns/rbtdb.c, lib/dns/resolver.c and lib/ns/query.c.
  • CVE-2026-13204
• SECURITY UPDATE: forged DNSSEC-validated NXDOMAIN responses
  • debian/patches/CVE-2026-19941.patch: require NSEC wildcard proofs to be signed by the same zone as the NOQNAME proof in lib/dns/validator.c and lib/dns/include/dns/validator.h.
  • CVE-2026-19941
• SECURITY UPDATE: DNSSEC validation bypass via NSEC3 impersonation
  • debian/patches/CVE-2026-10723.patch: check that the NSEC3 signer matches the owning zone in lib/dns/dnssec.c and lib/isc/result.c.
  • CVE-2026-10723
• SECURITY UPDATE: excessive CPU use validating crafted DNSSEC responses
  • debian/patches/CVE-2026-19668.patch: bound the DS-to-DNSKEY matching during DNSSEC validation and make the exhausted quota terminal in lib/dns/validator.c and lib/dns/resolver.c.
  • CVE-2026-19668
• SECURITY UPDATE: use-after-free of cached NOQNAME proofs
  • debian/patches/CVE-2026-19662.patch: keep the cache slabheader that owns a NOQNAME or closest-encloser proof referenced while the proof rdatasets are in use in lib/dns/rbtdb.c.
  • CVE-2026-19662
• SECURITY UPDATE: out-of-zone data above the apex treated as a zone cut
  • debian/patches/CVE-2026-78301.patch: ignore nodes above the zone origin in RBT zone database lookups in lib/dns/rbtdb.c.
  • CVE-2026-78301
• SECURITY UPDATE: sparsely signed incoming zone transfers accepted
  • debian/patches/CVE-2026-19033.patch: require a TSIG on every message of an incoming zone transfer in lib/dns/xfrin.c.
  • CVE-2026-19033
• SECURITY UPDATE: memory amplification via duplicate singleton records
  • debian/patches/CVE-2026-75029.patch: skip duplicate singleton records when parsing DNS messages in lib/dns/message.c.
  • CVE-2026-75029
• SECURITY UPDATE: DNSSEC downgrade of secure delegations via NSEC3 from an unrelated sibling zone
  • debian/patches/CVE-2026-77119.patch: ignore NSEC3 records whose owner zone does not enclose the DS name in the insecure delegation proof in lib/dns/validator.c.
  • CVE-2026-77119
• SECURITY UPDATE: invalid signed wildcard records accepted
  • debian/patches/CVE-2026-11721.patch: reject RRSIG records whose labels field is lower than the signer label count when parsing and verifying in lib/dns/rdata/generic/rrsig_46.c and lib/dns/dnssec.c, and do not sign out-of-zone records in bin/dnssec/dnssec-signzone.c.
  • CVE-2026-11721

Resource exhaustion via malformed DNSKEY handling (CVE-2025-8677). Cache poisoning attacks with unsolicited RRs (CVE-2025-40778). Cache poisoning due to weak PRNG (CVE-2025-40780).

These are all security issues fixed in the bind-9.20.15-1.1 package on the GA media of openSUSE Tumbleweed.

This update for bind fixes the following issues:

• Upgrade to release 9.20.15 Security Fixes:

  • CVE-2025-40778: Fixed cache poisoning attacks with unsolicited RRs (bsc#1252379)
  • CVE-2025-40780: Fixed cache poisoning due to weak PRNG (bsc#1252380)
  • CVE-2025-8677: Fixed resource exhaustion via malformed DNSKEY handling (bsc#1252378)

  New Features:

  • Add dnssec-policy keys configuration check to named-checkconf.
  • Add a new option manual-mode to dnssec-policy.
  • Add a new option servfail-until-ready to response-policy zones.
  • Support for parsing HHIT and BRID records has been added.
  • Support for parsing DSYNC records has been added.

  Removed Features:

  • Deprecate the tkey-gssapi-credential statement.
  • Obsolete the tkey-domain statement.

  Feature Changes:

  • Add deprecation warnings for RSASHA1, RSASHA1-NSEC3SHA1, and DS digest type 1.

  Bug Fixes:

  • Missing DNSSEC information when CD bit is set in query.
  • rndc sign during ZSK rollover will now replace signatures.
  • Use signer name when disabling DNSSEC algorithms.
  • Preserve cache when reload fails and reload the server again.
  • Prevent spurious SERVFAILs for certain 0-TTL resource records.
  • Fix unexpected termination if catalog-zones had undefined default-primaries.
  • Stale RRsets in a CNAME chain were not always refreshed.
  • Add RPZ extended DNS error for zones with a CNAME override policy configured.
  • Fix dig +keepopen option.
  • Log dropped or slipped responses in the query-errors category.
  • Fix synth-from-dnssec not working in some scenarios.
  • Clean enough memory when adding new ADB names/entries under memory pressure.
  • Prevent spurious validation failures.
  • Ensure file descriptors 0-2 are in use before using libuv [bsc#1230649]

This update for bind fixes the following issues:

Upgrade to release 9.20.15:

• CVE-2025-8677: DNSSEC validation fails if matching but invalid DNSKEY is found (bsc#1252378).
• CVE-2025-40778: Address various spoofing attacks (bsc#1252379).
• CVE-2025-40780: Cache-poisoning due to weak pseudo-random number generator (bsc#1252380).

This update for bind fixes the following issues:

• CVE-2025-8677: DNSSEC validation fails if matching but invalid DNSKEY is found (bsc#1252378).
• CVE-2025-40778: Address various spoofing attacks (bsc#1252379).
• CVE-2025-40780: Cache-poisoning due to weak pseudo-random number generator (bsc#1252380).

This update for bind fixes the following issues:

• Upgrade to release 9.20.15 Security Fixes:

  • CVE-2025-40778: Fixed cache poisoning attacks with unsolicited RRs (bsc#1252379)
  • CVE-2025-40780: Fixed cache poisoning due to weak PRNG (bsc#1252380)
  • CVE-2025-8677: Fixed resource exhaustion via malformed DNSKEY handling (bsc#1252378)

  New Features:

  • Add dnssec-policy keys configuration check to named-checkconf.
  • Add a new option manual-mode to dnssec-policy.
  • Add a new option servfail-until-ready to response-policy zones.
  • Support for parsing HHIT and BRID records has been added.
  • Support for parsing DSYNC records has been added.

  Removed Features:

  • Deprecate the tkey-gssapi-credential statement.
  • Obsolete the tkey-domain statement.

  Feature Changes:

  • Add deprecation warnings for RSASHA1, RSASHA1-NSEC3SHA1, and DS digest type 1.

  Bug Fixes:

  • Missing DNSSEC information when CD bit is set in query.
  • rndc sign during ZSK rollover will now replace signatures.
  • Use signer name when disabling DNSSEC algorithms.
  • Preserve cache when reload fails and reload the server again.
  • Prevent spurious SERVFAILs for certain 0-TTL resource records.
  • Fix unexpected termination if catalog-zones had undefined default-primaries.
  • Stale RRsets in a CNAME chain were not always refreshed.
  • Add RPZ extended DNS error for zones with a CNAME override policy configured.
  • Fix dig +keepopen option.
  • Log dropped or slipped responses in the query-errors category.
  • Fix synth-from-dnssec not working in some scenarios.
  • Clean enough memory when adding new ADB names/entries under memory pressure.
  • Prevent spurious validation failures.
  • Ensure file descriptors 0-2 are in use before using libuv [bsc#1230649]

Zuyao Xu and Xiang Li discovered that Bind incorrectly handled certain malformed DNSKEY records. A remote attacker could possibly use this issue to cause Bind to consume resources, resulting in a denial of service. (CVE-2025-8677)

Yuxiao Wu, Yunyi Zhang, Baojun Liu, and Haixin Duan discovered that Bind incorrectly accepted certain records from answers. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40778)

Amit Klein and Omer Ben Simhon discovered that Bind used a weak PRNG. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40780)

USN-7836-1 fixed vulnerabilities in Bind. This update provides the corresponding fixes for Ubuntu 20.04 LTS.

Original advisory details:

Zuyao Xu and Xiang Li discovered that Bind incorrectly handled certain malformed DNSKEY records. A remote attacker could possibly use this issue to cause Bind to consume resources, resulting in a denial of service. (CVE-2025-8677)

Yuxiao Wu, Yunyi Zhang, Baojun Liu, and Haixin Duan discovered that Bind incorrectly accepted certain records from answers. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40778)

Amit Klein and Omer Ben Simhon discovered that Bind used a weak PRNG. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40780)

Zuyao Xu and Xiang Li discovered that Bind incorrectly handled certain malformed DNSKEY records. A remote attacker could possibly use this issue to cause Bind to consume resources, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, and Ubuntu 18.04 LTS. (CVE-2025-8677)

Yuxiao Wu, Yunyi Zhang, Baojun Liu, and Haixin Duan discovered that Bind incorrectly accepted certain records from answers. A remote attacker could possibly use this issue to perform a cache poisoning attack. This issue only affected Ubuntu 18.04 LTS. (CVE-2025-40778)

Samy Medjahed discovered that Bind incorrectly handled insecure delegation validation. A remote attacker could possibly use this issue to cause excessive NSEC3 iterations, consuming CPU resources, and leading to a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-1519)

It was discovered that Bind incorrectly accepted NSEC3 records whose signer name did not match the owning zone. A remote attacker could possibly use this issue to perform NSEC3 impersonation attacks, bypassing DNSSEC validation. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-10723)

It was discovered that Bind incorrectly handled Key Records using the PRIVATEDNS algorithm. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS. (CVE-2026-10822)

It was discovered that Bind incorrectly handled wildcard CNAME expansion in Response Policy Zones. A remote attacker could possibly use this issue to bypass configured RPZ policies. This issue only affected Ubuntu 20.04 LTS. (CVE-2026-11331)

It was discovered that Bind incorrectly tracked memory usage in the DNS cache. A remote attacker could possibly use this issue to cause Bind to use memory beyond configured limits, leading to a denial of service. This issue only affected Ubuntu 20.04 LTS. (CVE-2026-11622)

It was discovered that Bind incorrectly handled signed wildcard records with label count discrepancies and RRSIG validation. A remote attacker could possibly use this issue to perform cache poisoning attacks. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-11721)

It was discovered that Bind incorrectly handled DNSSEC validation when a domain was covered by both NSEC and NSEC3 records with only one type having an RRSIG. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-13204)

It was discovered that Bind incorrectly validated out-of-zone NSEC next owner names during DNSSEC validation. A remote attacker could possibly use this issue to bypass DNSSEC validation. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-13321)

It was discovered that Bind incorrectly served zone transfer data before verifying the TSIG signature on multi-message transfers. A remote attacker could possibly use this issue to send unauthorized zone contents to a secondary server. (CVE-2026-19033)

It was discovered that Bind incorrectly handled the lifetime of cached DNSSEC proofs, leading to a use-after-free. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 26.04 LTS. (CVE-2026-19662)

It was discovered that Bind incorrectly handled certain malformed answers when configured to use DNS64. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. (CVE-2026-19666)

It was discovered that Bind incorrectly handled oversized negative answers when storing them in the…