An issue was discovered in OpenDKIM through 2.10.3, and 2.11.x through 2.11.0-Beta2. It fails to keep track of ordinal numbers when removing fake Authentication-Results header fields, which allows a remote attacker to craft an e-mail message with a fake sender address such that programs that rely on Authentication-Results from OpenDKIM will treat the message as having a valid DKIM signature when in fact it has none.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Opendkim | Opendkim | * | 2.10.3 (including) |
| Opendkim | Opendkim | 2.11.0-beta0 (including) | 2.11.0-beta0 (including) |
| Opendkim | Opendkim | 2.11.0-beta1 (including) | 2.11.0-beta1 (including) |
| Opendkim | Opendkim | 2.11.0-beta2 (including) | 2.11.0-beta2 (including) |
| Opendkim | Ubuntu | bionic | * |
| Opendkim | Ubuntu | focal | * |
| Opendkim | Ubuntu | kinetic | * |
| Opendkim | Ubuntu | lunar | * |
| Opendkim | Ubuntu | mantic | * |
| Opendkim | Ubuntu | oracular | * |
| Opendkim | Ubuntu | plucky | * |
| Opendkim | Ubuntu | trusty | * |
| Opendkim | Ubuntu | xenial | * |