It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default). This issue affects BIND 9 versions 9.11.0 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.
| Vendor | Product | Versions |
|---|---|---|
| isc | bind | 9.11.0, 9.20.0, 9.21.0, 9.11.3-S1, 9.20.9-S1 |
Downstream vendors/products affected by this vulnerability
| Vendor | Product | Source | Confidence |
|---|---|---|---|
| debian | debian linux | cert_advisory | 90% |
| internet systems consortium | bind | cert_advisory | 90% |
Updated severity from HIGH to CRITICAL and added CWE-20 (Improper Input Validation) based on article classification.
Initial creation
