Is CVE-2026-75029 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-75029 being exploited in the wild.

How severe is CVE-2026-75029?

Medium severity, with a CVSS score of 5.3, published 16 September 2026.

Which products and versions are affected?

Isc Bind 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, 9.20.9-S1 through 9.20.27-S1.

Is there a fix for CVE-2026-75029?

A patch was published on 2026-09-16: BIND 9.18.51, 9.20.28, and 9.21.26 released with fixes Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-75029 attacked?

It is attacked over the network, in an operating system.

Am I affected by CVE-2026-75029?

Check whether you run Isc Bind at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-75029: ISC BIND DNS cache memory exhaustion in query responses

CVE-2026-75029 · Severity: medium · CVSS 5.3 · Published 2026-09-16

BIND is a widely-deployed DNS resolver software used by organizations to translate domain names to IP addresses. An attacker can send specially-crafted DNS responses containing duplicate records (like SOA records) to exhaust the resolver's memory through its negative cache, potentially causing performance degradation or service unavailability.

Technologies: Isc Bind. Vendors: Isc.

Quick answers

Is CVE-2026-75029 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-75029 being exploited in the wild.
How severe is CVE-2026-75029?: Medium severity, with a CVSS score of 5.3, published 16 September 2026.
Which products and versions are affected?: Isc Bind 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, 9.20.9-S1 through 9.20.27-S1.
Is there a fix for CVE-2026-75029?: A patch was published on 2026-09-16: BIND 9.18.51, 9.20.28, and 9.21.26 released with fixes Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-75029 attacked?: It is attacked over the network, in an operating system.
Am I affected by CVE-2026-75029?: Check whether you run Isc Bind at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A flaw in BIND's DNS query response handling allows an attacker to send multiple copies of records that should exist only once (e.g., SOA records) in a single response. When the RDATA (resource record data) is identical across all copies, BIND appends each record to its in-memory negative cache instead of deduplicating, leading to unbounded memory growth. This is a network-reachable vulnerability requiring no authentication; an attacker can repeatedly send malicious responses to trigger memory exhaustion. The vulnerability affects BIND 9.11.0–9.18.50, 9.20.0–9.20.27, 9.21.0–9.21.25, and their -S1 (FIPS) variants. Patches are available in BIND 9.18.51+, 9.20.28+, and 9.21.26+.

Affected products

ISC BIND 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, 9.20.9-S1 through 9.20.27-S1

Timeline

2026-09-16: disclosed: CVE-2026-75029 published
2026-09-16: patched: BIND 9.18.51, 9.20.28, and 9.21.26 released with fixes

References

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