repetitions

• Description: Can you make sense of this file?
• Difficulty: Easy

---

🔎 Solution

Upon inspecting the content of the provided file, it's immediately clear that it contains a Base64-encoded string.

┌──(kali㉿kali)-[~/Desktop]
└─$ cat enc_flag            
VmpGU1EyRXlUWGxTYmxKVVYwZFNWbGxyV21GV1JteDBUbFpPYWxKdFVsaFpWVlUxWVZaS1ZWWnVh
RmRXZWtab1dWWmtSMk5yTlZWWApiVVpUVm10d1VWZFdVa2RpYlZaWFZtNVdVZ3BpU0VKeldWUkNk
MlZXVlhoWGJYQk9VbFJXU0ZkcVRuTldaM0JZVWpGS2VWWkdaSGRXCk1sWnpWV3hhVm1KRk5XOVVW
VkpEVGxaYVdFMVhSbFZrTTBKVVZXMTRWMDVHV2toalJYUlhDazFyV25sVVZXaHpWakpHZEdWRlZs
aGkKYlRrelZERldUMkpzUWxWTlJYTkxDZz09Cg==

After performing an initial decode, the result is yet another Base64 string.

┌──(kali㉿kali)-[~/Desktop]
└─$ cat enc_flag | base64 -d           
VjFSQ2EyTXlSblJUV0dSVllrWmFWRmx0TlZOalJtUlhZVVU1YVZKVVZuaFdWekZoWVZkR2NrNVVX
bUZTVmtwUVdWUkdibVZXVm5WUgpiSEJzWVRCd2VWVXhXbXBOUlRWSFdqTnNWZ3BYUjFKeVZGZHdW
MlZzVWxaVmJFNW9UVVJDTlZaWE1XRlVkM0JUVW14V05GWkhjRXRXCk1rWnlUVWhzVjJGdGVFVlhi
bTkzVDFWT2JsQlVNRXNLCg==

Repeating this process 5 more times reveals the final flag.

┌──(kali㉿kali)-[~/Desktop]
└─$ echo "VjFSQ2EyTXlSblJUV0dSVllrWmFWRmx0TlZOalJtUlhZVVU1YVZKVVZuaFdWekZoWVZkR2NrNVVX
bUZTVmtwUVdWUkdibVZXVm5WUgpiSEJzWVRCd2VWVXhXbXBOUlRWSFdqTnNWZ3BYUjFKeVZGZHdW
MlZzVWxaVmJFNW9UVVJDTlZaWE1XRlVkM0JUVW14V05GWkhjRXRXCk1rWnlUVWhzVjJGdGVFVlhi
bTkzVDFWT2JsQlVNRXNLCg==" | base64 -d
V1RCa2MyRnRTWGRVYkZaVFltNVNjRmRXYUU5aVJUVnhWVzFhYVdGck5UWmFSVkpQWVRGbmVWVnVR
bHBsYTBweVUxWmpNRTVHWjNsVgpXR1JyVFdwV2VsUlZVbE5oTURCNVZXMWFUd3BTUmxWNFZHcEtW
MkZyTUhsV2FteEVXbm93T1VOblBUMEsK
                                                                                                                      
┌──(kali㉿kali)-[~/Desktop]
└─$ echo "V1RCa2MyRnRTWGRVYkZaVFltNVNjRmRXYUU5aVJUVnhWVzFhYVdGck5UWmFSVkpQWVRGbmVWVnVR
bHBsYTBweVUxWmpNRTVHWjNsVgpXR1JyVFdwV2VsUlZVbE5oTURCNVZXMWFUd3BTUmxWNFZHcEtW
MkZyTUhsV2FteEVXbm93T1VOblBUMEsK" | base64 -d
WTBkc2FtSXdUbFZTYm5ScFdWaE9iRTVxVW1aaWFrNTZaRVJPYTFneVVuQlpla0pyU1ZjME5GZ3lV
WGRrTWpWelRVUlNhMDB5VW1aTwpSRlV4VGpKV2FrMHlWamxEWnowOUNnPT0K
                                                                                                                      
┌──(kali㉿kali)-[~/Desktop]
└─$ echo "WTBkc2FtSXdUbFZTYm5ScFdWaE9iRTVxVW1aaWFrNTZaRVJPYTFneVVuQlpla0pyU1ZjME5GZ3lV
WGRrTWpWelRVUlNhMDB5VW1aTwpSRlV4VGpKV2FrMHlWamxEWnowOUNnPT0K" | base64 -d
Y0dsamIwTlVSbnRpWVhObE5qUmZiak56ZEROa1gyUnBZekJrSVc0NFgyUXdkMjVzTURSa00yUmZO
RFUxTjJWak0yVjlDZz09Cg==
                                                                                                                      
┌──(kali㉿kali)-[~/Desktop]
└─$ echo "Y0dsamIwTlVSbnRpWVhObE5qUmZiak56ZEROa1gyUnBZekJrSVc0NFgyUXdkMjVzTURSa00yUmZO
RFUxTjJWak0yVjlDZz09Cg==" | base64 -d
cGljb0NURntiYXNlNjRfbjNzdDNkX2RpYzBkIW44X2Qwd25sMDRkM2RfNDU1N2VjM2V9Cg==
                                                                                                                      
┌──(kali㉿kali)-[~/Desktop]
└─$ echo "cGljb0NURntiYXNlNjRfbjNzdDNkX2RpYzBkIW44X2Qwd25sMDRkM2RfNDU1N2VjM2V9Cg==" | base64 -d
picoCTF{base64_n3st3d_dic0d!n8_d0wnl04d3d_4557ec3e}

🚩Flag

picoCTF{base64_n3st3d_dic0d!n8_d0wnl04d3d_4557ec3e}