CVE-2026-93600
CVE-2026-93600
rustls-webpki (rustls/webpki) versions 0.101.0 through 0.103.11 and 0.104.0-alpha releases before 0.104.0-alpha.6 ignore X.509 name constraints that apply to URI names, causing such constraints to be accepted rather than enforced. Because name constraints are restrictions on otherwise properly issued certificates, the flaw is only reachable after successful signature verification and requires a misissued certificate to exploit; the library also provides no API for asserting URI names, and URI name constraints are otherwise unimplemented. Versions 0.103.12 and 0.104.0-alpha.6 reject URI name constraints unconditionally.
Vulnerability class: Improper Certificate Validation
CVSS v3 metric
CVSS v3 base score 2.2 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N.
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-93600?
- CVE-2026-93600 is a low-severity vulnerability, classified under Improper Certificate Validation. CVSS score: 2.2/10. Published 2026-09-18.
- How severe is CVE-2026-93600?
- Low severity. CVSS v3 base score is 2.2 out of 10.