MEDIUM5.3

PYSEC-2026-2268

Quick fix

PYSEC-2026-2268 — pyopenssl: upgrade to the fixed version with the command below.

pip install --upgrade 'pyopenssl>=26.0.0'

Details

pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version 26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception, this would result in a connection being accepted. If a user was relying on this callback for any security-sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now result in rejecting the connection.

Are you affected?

Enter the version of the package you're using.

Affected packages

PyPI/pyopenssl

Introduced in: 0.14Fixed in: 26.0.0

Fixpip install --upgrade 'pyopenssl>=26.0.0'

References

https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst#L27[ADVISORY]
https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424[ADVISORY]
https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa0[FIX]