CVE-2026-75029 PUBLISHED

Message parser retains every identical singleton RDATA, enabling wire-to-work amplification

Assigner: isc
Reserved: 17.08.2026 Published: 16.09.2026 Updated: 16.09.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS Score: 5.3

Product Status

Vendor ISC
Product BIND 9
Versions Default: unaffected
  • affected from 9.11.0 to 9.18.50 (incl.)
  • affected from 9.20.0 to 9.20.27 (incl.)
  • affected from 9.21.0 to 9.21.25 (incl.)
  • affected from 9.11.3-S1 to 9.18.50-S1 (incl.)
  • affected from 9.20.9-S1 to 9.20.27-S1 (incl.)

Exploits

This flaw was discovered in internal testing. We are not aware of any active exploits.

Workarounds

No workarounds known.

Solutions

Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.29, 9.21.26, or 9.20.29-S1.

References

Problem Types

  • CWE-405 Asymmetric Resource Consumption (Amplification) CWE

Impacts

  • An attacker may be able to cause `named` to consume memory beyond the configured limits.