OpenBSD kernel version <= 6.5 can be forced to create long chains of TCP SACK holes that causes very expensive calls to tcp_sack_option() for every incoming SACK packet which can lead to a denial of service.
The product performs a data query with a large number of joins and sub-queries on a large data table.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Openbsd | Openbsd | * | 6.5 (including) |
This issue can make the product perform more slowly. If the relevant code is reachable by an attacker, then this performance problem might introduce a vulnerability. While the interpretation of “large data table” and “large number of joins or sub-queries” may vary for each product or developer, CISQ recommends a default of 1 million rows for a “large” data table, a default minimum of 5 joins, and a default minimum of 3 sub-queries.