Comment by aftbit

17 hours ago

Or - you can just upgrade pip with a SHA hash pin, or set the magic env vars to use the system bundle.

You do need to be careful about creating new venvs with the old version of pip bundled in ensurepip in older Python releases. `uv` kindly patches that to newest pip, but not every Python binary does.

  python -m pip install "pip @ https://files.pythonhosted.org/packages/3f/06/3e4420302363fbb71be3c7f35ce042f54bfca330e3e66b3a2e3c4cca579f/pip-26.2.2-py3-none-any.whl#sha256=fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70"

Or alternatively, on Debian with fixed system cert chain:

  PIP_USE_DEPRECATED=legacy-certs PIP_CERT=/etc/ssl/certs/ca-certificates.crt python -m pip install --upgrade "pip>=26.2.2"

https://discuss.python.org/t/avoiding-compromised-certificat...

4 comments

aftbit

zahlman 4 hours ago

I had a pretty fun time with it myself. Rather than a system package for pip, or the `ensurepip`-provided one, I've been using the copy managed by pipx. I had to:

* Update system certificates

* Locate that pip and directly invoke it to self-update with hash pinning, rather than going through pipx

* Fix a few stray venvs that contained their own pip

* Use the fixed pipx to update uv (although I guess the uv self-update should work even for a pipx-installed copy?)

The legacy-certs hint is neat. I did it the first way but would rather not have since I'm on Mint.

tetha 15 hours ago

Good to know. Does the first invocation recompute and check the hash of the wheel locally afterwards to ensure integrity?

aftbit 14 hours ago

Yep! I tested it with my own vibe-coded MITM proxy that hijacks pypi installations, which I created for ~$0.30 spend on DeepSeek API.

    $ python -m pip --no-cache install "pip @ https://files.pythonhosted.org/packages/3f/06/3e4420302363fbb71be3c7f35ce042f54bfca330e3e66b3a2e3c4cca579f/pip-26.2.2-py3-none-any.whl#sha256=fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70"
    Collecting pip @ https://files.pythonhosted.org/packages/3f/06/3e4420302363fbb71be3c7f35ce042f54bfca330e3e66b3a2e3c4cca579f/pip-26.2.2-py3-none-any.whl#sha256=fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70
      Downloading pip-26.2.2-py3-none-any.whl (1.8 MB)
         ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1.8/1.8 MB 570.0 MB/s  0:00:00
    ERROR: THESE PACKAGES DO NOT MATCH THE HASHES FROM THE REQUIREMENTS FILE. If you have updated the package versions, please update the hashes. Otherwise, examine the package contents carefully; someone may have tampered with them.
        pip @ https://files.pythonhosted.org/packages/3f/06/3e4420302363fbb71be3c7f35ce042f54bfca330e3e66b3a2e3c4cca579f/pip-26.2.2-py3-none-any.whl#sha256=fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70 from https://files.pythonhosted.org/packages/3f/06/3e4420302363fbb71be3c7f35ce042f54bfca330e3e66b3a2e3c4cca579f/pip-26.2.2-py3-none-any.whl#sha256=fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70:
            Expected sha256 fd7f4dfa8190e014013b9f08f3e973f4e4c26ffd179a204895533a7254813a70
                 Got        8c448177668e735cdde7d6178694b90c084ba18559348cc394c4b1546eeec89c

The second one works too:

    $ PIP_USE_DEPRECATED=legacy-certs PIP_CERT=/etc/ssl/certs/ca-certificates.crt python -m pip install --no-cache --upgrade "pip>=26.2.2"
    WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082)'))': /simple/pip/
    WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082)'))': /simple/pip/
    WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082)'))': /simple/pip/
    WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082)'))': /simple/pip/
    WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082)'))': /simple/pip/
    Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1082) - skipping
    ERROR: Could not find a version that satisfies the requirement pip>=26.2.2 (from versions: none)
    ERROR: No matching distribution found for pip>=26.2.2

As compared with a naive installation through the proxy:

    $ python -m pip --no-cache install 'pip>=26.2.2'
    Collecting pip>=26.2.2
      Downloading pip-26.2.2-py3-none-any.whl.metadata (4.6 kB)
    Downloading pip-26.2.2-py3-none-any.whl (1.8 MB)
       ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1.8/1.8 MB 775.3 MB/s  0:00:00
    Installing collected packages: pip
      Attempting uninstall: pip
        Found existing installation: pip 26.2.1
        Uninstalling pip-26.2.1:
          Successfully uninstalled pip-26.2.1
    Successfully installed pip-26.2.2

    $ cat venv/lib/python3.14/site-packages/sni_proxy_sentinel.txt
    SNI proxy lab sentinel. This file is inert.

tetha 14 hours ago

Oh nice. Then I have to thank you for a possible non-horrible upgrade path. If you were close by, I'd invite you for some icecream or a round of pool :)