CVE-2026-75029 Message parser retains every identical singleton RDATA, enabling wire-to-work amplification
An attacker can cause excessive memory usage in the BIND DNS server by sending duplicate RDATA records, potentially leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-75029?
CVE-2026-75029 is a medium-severity denial of service vulnerability in ISC BIND 9, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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 lead to other memory attack vectors. 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.
Weakness: CWE-405
Which versions are affected by CVE-2026-75029?
How do I fix CVE-2026-75029?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-75029 being exploited?
There is no known exploitation of CVE-2026-75029 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-75029, AZL-103353, BELL-CVE-2026-75029, DEBIAN-CVE-2026-75029, ECHO-2d3a-cd7f-806b, GHSA-crh2-6h8j-h25c and 4 more.