CVE-2026-10723

Incorrect acceptance of NSEC3 records

BIND may accept incorrect child-zone NSEC3 records as valid, which could allow an attacker to forge authenticated NXDOMAIN responses. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-11605

Unnecessary validation of DNSSEC signed records

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 waste disproportionate CPU time. This issue affects BIND 9 versions 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and 9.20.9-S1 through 9.20.24-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2026-12617

Record ordering based unexpected exit with CNAME or DNAME

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 query but delays the DNAME response and later responds negatively, `named` may quit unexpectedly. Or, if a client queries for a CNAME and A record for the same name to the resolver, and the authoritative server responds positively to the A query but delays the CNAME response and later responds with a self-referential CNAME, the same failure may occur. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-94300

Concurrent GSS-TSIG messages corrupt memory

Replaying GSS-TSIG signed UDP messages can result in memory corruption in "`named`". An attacker who can capture a previously signed UDP message can replay it while the negotiated TSIG key is still valid. By also sending crafted queries to a zone the attacker controls, the attacker may potentially achieve remote code execution. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2026-19630

Amplified resource exhaustion in inbound message processing

In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with no limit imposed by BIND. A DNS message with a maliciously large number of such structures will cause BIND to consume disproportionate amounts of CPU time and memory during processing. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2026-96888

Named may terminate unexpectedly when a redirect zone is used with strict QNAME minimization

A BIND resolver that is configured with both a "redirect" zone and "qname-minimization strict" may abort with an assertion failure while processing the redirect. This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2026-97313

Specific RPZ configurations and query patterns may result in an unexpected exit

A recursive BIND server that receives a query with recursion desired (RD=1) followed by a non-recursive query (RD=0) may exit with an assertion failure, resulting in a denial of service. To be vulnerable, the BIND server must allow recursive queries and have at least two RPZ zones configured: one with the default setting of "recursive-only yes", and the other with "recursive-only no". This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2026-81736

Remote CPU denial of service through cached SVCB/HTTPS AliasMode trees

If a BIND resolver has cached a tree of SVCB/HTTPS AliasMode records, and is then queried for the root of that tree, the resolver will spend disproportionate CPU time constructing the response. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-19667

Remote assertion failure via 16-bit length truncation in `dns_ncache_add()`

If an attacker-controlled authoritative server can produce a negative answer that is exactly 65536 bytes, then a flaw in `named` results in a negative cache entry of 0 bytes. When this entry is subsequently read, `named` aborts. 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 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-81563

SVCB AliasMode additional-data error leaks qpcache references

A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-80274

Validating resolver can abort while caching a mismatched NOQNAME proof

If a BIND resolver sends a query for a DNSSEC-signed authoritative zone, and the authoritative server replies with a valid wildcard answer and signed NSEC3 proof, followed by an unsigned NSEC at the same owner name, it will trigger an unexpected program exit. 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 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-76163

named aborts on a TKEY query when the user configuration has no global options statement

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 9.20.9-S1 through 9.20.27-S1.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind Bind 9

CVE-2026-5946

Invalid handling of CLASS != IN

Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.

CVSS 3.1 · 7.5 High EPSS 1.9% KEV · Not listed

Vendors

Isc Redhat

Products

Bind Bind 9 Hummingbird

CVE-2025-40775

DNS message with invalid TSIG causes an assertion failure

When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it. If the TSIG contains an invalid value in the algorithm field, BIND immediately aborts with an assertion failure. This issue affects BIND 9 versions 9.20.0 through 9.20.8 and 9.21.0 through 9.21.7.

CVSS 3.1 · 7.5 High EPSS 15.4% KEV · Not listed

Vendors

Isc

Products

Bind 9

CVE-2025-8677

Resource exhaustion via malformed DNSKEY handling

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.

CVSS 3.1 · 7.5 High EPSS 11.3% KEV · Not listed

Vendors

Isc

Products

Bind 9

CVE-2025-40780

Cache poisoning due to weak PRNG

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.

CVSS 3.1 · 8.6 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind 9

CVE-2025-40778

Cache poisoning attacks with unsolicited RRs

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.

CVSS 3.1 · 8.6 High EPSS < 1% KEV · Not listed

Vendors

Isc

Products

Bind 9

CVE-2023-5517

Querying RFC 1918 reverse zones may cause an assertion failure when "nxdomain-redirect" is enabled

A flaw in query-handling code can cause `named` to exit prematurely with an assertion failure when: - `nxdomain-redirect <domain>;` is configured, and - the resolver receives a PTR query for an RFC 1918 address that would normally result in an authoritative NXDOMAIN response. This issue affects BIND 9 versions 9.12.0 through 9.16.45, 9.18.0 through 9.18.21, 9.19.0 through 9.19.19, 9.16.8-S1 through 9.16.45-S1, and 9.18.11-S1 through 9.18.21-S1.

CVSS 3.1 · 7.5 High EPSS 1.3% KEV · Not listed

Vendors

Fedoraproject Isc Netapp and 1 more

Products

Fedora Bind Bind 9 and 3 more