An issue was discovered in Heimdal Thor agent versions 3.4.2 and before on Windows and 2.6.9 and before on macOS, allows attackers to cause a denial of service (DoS) via the Threat To Process Correlation threat prevention module. NOTE: Heimdal asserts this is not a valid vulnerability. Their DNS Security for Endpoint solution includes an optional feature to provide extra information on the originating process that made a DNS request. The lack of process identification in DNS logs is therefore falsely categorized as a DoS issue.
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Thor | Heimdalsecurity | * | 3.5.3 (including) |
Attackers can create crafted inputs that
intentionally cause the regular expression to use
excessive backtracking in a way that causes the CPU
consumption to spike.