Multiple serious vulnerabilities have been found in PuTTY. Malicious users can exploit these vulnerabilities to cause denial of service, obtain sensitive information or possibly execute arbitrary code. Below is a complete list of vulnerabilities

1. An integer overflow can be exploited remotely via a specially designed RSA key;
2. Improper work with memory can be exploited locally;
3. Buffer overflow and underflow can be exploited remotely via a specially designed DSA signature;

PuTTY versions earlier than 0.62

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