Znuny before LTS 6.5.1 through 6.5.10 and 7.0.1 through 7.0.16 allows DoS/ReDos via email. Parsing the content of emails where HTML code is copied from Microsoft Word could lead to high CPU usage and block the parsing process.
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 |
|---|---|---|---|
| Znuny | Znuny | 6.0.0 (including) | 6.1.0 (excluding) |
| Znuny | Znuny | 6.5.1 (including) | 6.5.10 (including) |
| Znuny | Znuny | 7.0.1 (including) | 7.0.16 (including) |
| Znuny | Ubuntu | upstream | * |
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.