🐛 fix(periodic-update): refuse unverified HTTPS to PyPI by default#3122
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When the verified HTTPS request to ``https://pypi.org/pypi/<dist>/json`` failed, the periodic update retried with an unverified SSL context and used whatever it got back. The original reasoning was that the metadata is not sensitive, but the response drives the "latest wheel" decision, so a network-level attacker with a TLS handshake in the middle can quietly pin virtualenv to an older version and suppress security updates. Skip the fallback by default and abort the lookup instead. Hosts with broken trust stores that need the old behaviour can set ``VIRTUALENV_PERIODIC_UPDATE_INSECURE=1`` as an explicit escape hatch, logged at WARNING so it is visible in CI output.
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rahuldevikar
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Security hardening. When the verified HTTPS request to
https://pypi.org/pypi/<dist>/jsonfailed, the periodic update retried the request with an unverified SSL context and used whatever came back. The original comment justified this with 'the information we request is not sensitive', but the metadata drives the decision about which wheel version virtualenv considers 'up to date'. 🔒 A network-level attacker that can break the handshake can then pin virtualenv to an older seed wheel and silently suppress security updates.The fallback is now skipped by default. A failed verified request logs the error and returns
None, which the periodic update path already handles gracefully — no wheel bump happens and the run continues. Hosts with genuinely broken trust stores can opt back in by settingVIRTUALENV_PERIODIC_UPDATE_INSECURE=1, which is logged at WARNING so it shows up in CI output. The env var is documented indocs/how-to/usage.rstnext to the existing override knobs.