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CVE-2026-69248mediumCWE-295

python-cryptography verifier accepts wildcard DNS names allowing escape from permittedSubtrees

13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.9epss 0.2%
exploitation probability
0.2%top 92% of all CVEs
observed exploitation
nono source reports it
cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Prior to 49.0.0, 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.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
Affected products
pyca · cryptography