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cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. From 46.0.6 through 48.x, if an intermediate constrained CA permits the DNS name foo.example.com, and the leaf certificate has a wildcard in its DNS SAN of *.example.com, python-cryptography's verifier accepts the chain, allowing escape outside of the permitted names. The core issue is in DNSConstraint::matches (introduced via PR #14542 / 46.0.6), where a wildcard pattern was treated as matching a more-specific permitted constraint even though *.example.com can expand to sibling names such as bar.example.com outside foo.example.com. This allows acceptance of an invalid certificate chain. Versions prior to 46.0.6 are not affected by this specific permittedSubtrees escape. This issue is fixed in 49.0.0.