It seems that SOCKS5 proxies somehow know the client's timezone (at least) or maybe even the precise datetime. I determined this because the proxy tears the connection in case the local timezone on the client machine is UTC, but the proxy works well if the client timezone is set to GMT+3.
I checked the request that is sent via https://httpbin.org/anything : it doesn't contain the Date:
header. Actually the request doesn't contain much at all:
{
"args": {},
"data": "",
"files": {},
"form": {},
"headers": {
"Accept": "*/*",
"Accept-Encoding": "deflate, gzip, br",
"Host": "httpbin.org",
"User-Agent": "Mozilla/5.0 (iPhone; CPU iPhone OS 10_2_1 like Mac OS X) AppleWebKit/602.1.50 (KHTML, like Gecko) CriOS/58.0.3029.83 Mobile/14D27 Safari/602.1",
"X-Amzn-Trace-Id": "Root=1-5ef44607-d2e19be825cf096c4f4facbc"
},
"json": null,
"method": "GET",
"origin": "180.6.40.101",
"url": "https://httpbin.org/anything"
}
So could you give me a hint on how SOCKS5 proxies can determine client's timezone or local time?