CVE-2026-34073cryptography has incomplete DNS name constraint enforcement on peer names
Updated under an hour ago ()
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It affects pyca cryptography and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. Prior to version 46.0.6, DNS name constraints were only validated against SANs within child certificates, and not the "peer name" presented during each validation. Consequently, cryptography would allow a peer named bar.example.com to validate against a wildcard leaf certificate for *.example.com, even if the leaf's parent certificate (or upwards) contained an excluded subtree constraint for bar.example.com. This issue has been patched in version 46.0.6.
- CVSS
- 1.7 LOW (v4.0, CNA)CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
- Weakness (CWE)
- CWE-295
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Modified
- Record last updated
- Oct 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
pyca cryptography pyca:cryptography (from the name) | before 46.0.6 | CNA record |
cryptography.io cryptography cryptography.io:cryptography | before 46.0.6 | NVD |
References
- https://github.com/pyca/cryptography/security/advisories/GHSA-m959-cc7f-wv43x-refsource-confirm, vendor-advisory
- https://www.kb.cert.org/vuls/id/948176
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.