Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a base argument that is larger than the mod argument, which causes the modpow function to write memory before the beginning of its buffer, and (2) remote malicious servers to cause a denial of service (client crash) and possibly execute arbitrary code via a large bignum during authentication.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Putty | Putty | 0.48 (including) | 0.48 (including) |
| Putty | Putty | 0.49 (including) | 0.49 (including) |
| Putty | Putty | 0.50 (including) | 0.50 (including) |
| Putty | Putty | 0.51 (including) | 0.51 (including) |
| Putty | Putty | 0.52 (including) | 0.52 (including) |
| Putty | Putty | 0.53 (including) | 0.53 (including) |
| Putty | Putty | 0.53b (including) | 0.53b (including) |
| Putty | Putty | 0.54 (including) | 0.54 (including) |