π¨ CRITICAL SECURITY VULNERABILITY IN SQUID WEB PROXY π¨
A 29-year-old bug dubbed "Squidbleed" (CVE-2026-47729) allows authorized proxy users to steal cleartext HTTP requests from other users β including passwords, session tokens, and sensitive data.
π THE DETAILS:
β’ Discovered with help from Anthropic's Claude Mythos Preview
β’ Classified as "trusted client" attack β someone already permitted to use the proxy
β’ Perfect for shared networks (schools, offices, public Wi-Fi) where attackers blend in as legitimate users
β’ Only affects cleartext HTTP traffic and TLS-terminating setups β normal HTTPS remains safe
β’ Requires access to an FTP server on port 21 (enabled by default on Squid)
π‘ WHY THIS MATTERS:
Most organizations run Squid on shared networks. This means one compromised user can snoop everyone else's traffic. The attack surface is small but the impact is severe β complete credential theft.
π MITIGATION:
β’ Patch to version 7.7 (verify the fix, not just the version number)
β’ DISABLE FTP entirely β Chromium dropped it years ago and most networks don't use it
β’ SUSE rates this CVSS 6.5 (confidentiality impact only)
The researchers' advice? Turn off FTP. It removes the attack vector for free.
This is a reminder that even "trusted" access can be weaponized in shared environments. Security through obscurity doesn't work when your colleague has admin rights to your proxy.


29-Year-Old Squid Proxy Bug
A 29-year-old bug in the Squid web proxy, dubbed Squidbleed and tracked as CVE-2026-47729, can let an authorized proxy user retrieve fragments of a...





