Burp problems after Windows update
Summary: PortSwigger reports that after March's Windows security update, Burp Proxy listeners running on the loopback interface stopped working because Microsoft changed the "localhost" entry in the Windows hosts file. The latest versions of Burp, both free and Pro editions, have been updated to work with the new hosts entry, and manually reverting to the old entry only fixes the problem temporarily since Windows silently restores the new one periodically.
Key Takeaway: A routine Windows security update silently broke loopback proxy listeners for Burp users, and the manual workaround does not hold because Windows reverts the hosts file on its own - so any team relying on local interception tooling had to wait for a vendor patch rather than fix it themselves.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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