FavFreak
Favicon hash–based reconnaissance tool for security research
...After fetching the favicon, it calculates a hash value and organizes the scanned domains, subdomains, or IP addresses according to these hashes. FavFreak then compares the generated hashes against a predefined fingerprint dictionary that maps known favicon hashes to specific technologies or services. If a match is found, it displays the corresponding technology information in the output, helping researchers quickly identify potential targets or related infrastructure. This approach is particularly useful during reconnaissance phases of security assessments because many web services share identical favicon hashes.