Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The cryptography package (PyPI) versions 45.0.0 up to but not including 49.0.0 is affected. A flaw in its certificate verifier lets a wildcard DNS name in a leaf certificate, such as *.example.com, pass checks against an intermediate CA's permitted name constraint for foo.example.com, so names outside the permitted set can be accepted. An attacker who can present such a certificate chain could get it accepted as valid. Upgrade to cryptography 49.0.0 or later. No workaround is given.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 6.9 | Medium | 4.0 | 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 | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0024, the 15th percentile, on 10 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Jul 2026, 13:43 UTC Published by the maintainers as a GitHub repository advisory
- 31 Oct 2026, 14:09 UTC First seen by agentprime
- 31 Oct 2026, 14:09 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-m2h6-j472-rp4c
- OSV: GHSA-m2h6-j472-rp4c
- github.com/pyca/cryptography/security/advisories/GHSA-m2h6-j472-rp4c
- nvd.nist.gov/vuln/detail/CVE-2026-69248
- github.com/pyca/cryptography/pull/14888
- github.com/pyca/cryptography/commit/286c89128
- github.com/pyca/cryptography/commit/4d035a4225965edeffd312079a510ef25fcfdcb2
- github.com/pyca/cryptography
- github.com/pypa/advisory-database/tree/main/vulns/cryptography/PYSEC-2026-3554.yaml