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TLS/SSL is broken over WLAN

RoflCopter4
Neighbour

My wireless connection does not appear to be working. It is very strange. The wired, ethernet connection works without problems. The wlan, though, is having problems on multiple devices, but it isn't broken either. I can ping remote servers successfully. I can even connect to them via unencrypted HTTP. But TLS/SSL is failing. Every encrypted connection ends in failure. Since this is most of the internet, it is effectively down. I have restarted the modem/router repeatedly, fiddled with date and time settings, the DNS server, and so on, and used multiple devices, and the problem has remained for more than 24 hours. Some of the failures complained about certificates, but most just closed the connection.

 

I can't really explain this. Am I alone here?

2 REPLIES 2

TELUS_Support
Official Support Team
Official Support Team

Hi! This suggests the issue is not with the devices themselves, but with how the router handles encrypted traffic over wireless, possibly due to:

Misconfigured MTU or packet fragmentation

Corrupt or failing Wi-Fi firmware in the router

A transparent proxy, firewall, or QoS setting that’s mangling SSL packets

Time sync issues (though you’ve already tried correcting that)

 

Steps to Troubleshoot Further

1. Check MTU (Maximum Transmission Unit) on Wireless

A misconfigured MTU can interfere with SSL handshakes.

On a wireless device, try:

If that fails, try smaller sizes (-s 1400, etc.).

If you're on Windows:

 If pings fail at higher packet sizes, you may need to reduce the MTU setting on your router (often under WAN or Advanced > Network settings) to something like 1400 or 1452.

 

2. Temporarily Disable Router Security Features

Some modern routers have security settings (e.g. “Safe Browsing,” “Parental Controls,” “SPI Firewall”) that can interfere with SSL.

Log into the router admin page

Look for:

DNS filtering or HTTPS inspection

QoS rules

SPI firewall or application-level gateways

Temporarily disable anything related to security or filtering to test.

 

3. Check Router Firmware

A recent update (or a failed/corrupted update) may have broken something.

Look up your router model online to see if others report similar issues.

If possible, rollback or reflash the firmware.

 

4. Try Custom DNS

You mentioned trying different DNS servers, but just to confirm — use 1.1.1.1 (Cloudflare) or 8.8.8.8 (Google).

Some ISPs redirect DNS over Wi-Fi differently than over Ethernet.

 

5. Bypass Router for Testing

To rule out the router:

Tether via a mobile hotspot and check HTTPS on the same device.

Or, if your modem and router are separate, try connecting directly to the modem via Wi-Fi (if possible).

 

6. Log Network Activity

On a desktop/laptop over Wi-Fi, try using:

Wireshark or browser dev tools (Network tab) to capture what’s happening during HTTPS failures.

Look for TLS handshake failure, RST packets, or certificate unknown.

cmd

ping -f -l 1472 google.com

bash

ping google.com -D -s 1472


If our reply resolved your issue, please click on Accept as Solution to help others in the community.

FuzzyLogic
Community Power User
Community Power User

What web browser? If possible maybe try an alternate to see if it may be related to a recent update to the browser.


Just a long time customer hoping to help.