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BREW-ansible@10-CVE-2026-69248 — python-cryptography verifier accepts wildcard DNS names allowing escape from permittedSubtrees

2026-10-03T01:35:41.087299+00:00

Affected: Homebrew: ansible@10

### Summary 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 which allows escaping outside of the permitted names.

### PoC

``` #!/usr/bin/env python3 """Standalone PoC: pyca's DNSConstraint::matches admits a too-broad wildcard SAN.

Setup: Sub-CA permitted constraint: dNSName = foo.example.com Leaf SAN: dNSName = *.example.com Expected: rejection (RFC 5280 §4.2.1.10 + standard wildcard semantics). Observed: pyca accepts; further, asks server-verifier whether the leaf is authoritative for `bar.example.com` and pyca answers yes — a sub-CA scope escape. """ import datetime from cryptography import x509 from cryptography.x509.oid import NameOID from cryptography.hazmat.primitives import hashes from cryptography.hazmat.primitives.asymmetric import ec from cryptography.x509.verification import ( PolicyBuilder, Store, ExtensionPolicy, Criticality, VerificationError, )

now = datetime.datetime(2027, 1, 1, tzinfo=datetime.timezone.utc) day = datetime.timedelta(days=1)

def build(subject, issuer, key, issuer_key, ca, exts=()): b = (x509.CertificateBuilder() .subject_name(subject).issuer_name(issuer) .public_key(key.public_key()) .serial_number(x509.random_serial_number()) .not_valid_before(now - 30 * day) .not_valid_after(now + 3650 * day) .add_extension(x509.Bas…

CVE-2026-69248 — python-cryptography verifier accepts wildcard DNS names allowing escape from permittedSubtrees

2026-10-03T01:35:41.087391+00:00

Affected: pyca cryptography

cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. In versions 45.0.0 through 48.0.0, 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 which allows escaping outside of the permitted names. The core issue is in DNSConstraint::matches, 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. This issue is fixed in 49.0.0.

GHSA-m2h6-j472-rp4c — python-cryptography verifier accepts wildcard DNS names allowing escape from permittedSubtrees

2026-10-03T01:35:41.087426+00:00

Affected: PyPI: cryptography

### PoC

``` #!/usr/bin/env python3 """Standalone PoC: pyca's DNSConstraint::matches admits a too-broad wildcard SAN.

now = datetime.datetime(2027, 1, 1, tzinfo=datetime.timezone.utc) day = datetime.timedelta(days=1)