When TLS 1.3 Silently Dies Inside Your Android Proxy
We run iProxy.online, a mobile proxy infrastructure. Our Android app turns phones into proxy servers across 100+ countries. Last year we shipped an advanced network health checker that runs a lot o...

Source: DEV Community
We run iProxy.online, a mobile proxy infrastructure. Our Android app turns phones into proxy servers across 100+ countries. Last year we shipped an advanced network health checker that runs a lot of probes through these proxies to a controlled server. That’s when things got weird. A small but noticeable percentage of devices started failing HTTPS checks. HTTP worked fine. The failure was always at the TLS handshake stage. And the behavior was completely non-deterministic: broken for two hours, then fine, then broken for five minutes, then fine again. What we saw The correlations were weak and noisy. Android v8-v9 devices showed up more often. Cheaper, lower-spec phones were overrepresented. The strongest signal was memory pressure on the device. When we could catch the failure in real time, the device was almost always low on available RAM. But metrics from memory-starved phones are unreliable by definition, so we couldn’t be sure this wasn’t survivorship bias. Two tracks of investigat