Description
BIND resolvers are vulnerable to an amplified resource consumption/exhaustion attack. If a victim resolver makes a query to a specially crafted zone, the resolver will consume disproportionate resources. 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.
Problem types
CWE-408 Incorrect Behavior Order - Early Amplification
Product status
9.11.0 (custom)
9.18.0 (custom)
9.20.0 (custom)
9.21.0 (custom)
9.11.3-S1 (custom)
9.18.11-S1 (custom)
9.20.9-S1 (custom)
Credits
ISC would like to thank Shuhan Zhang from Tsinghua University for bringing this vulnerability to our attention.
References
kb.isc.org/docs/cve-2026-3592 (CVE-2026-3592)
downloads.isc.org/isc/bind9/9.18.49
downloads.isc.org/isc/bind9/9.20.23
downloads.isc.org/isc/bind9/9.21.22