Improper Certificate Validation Affecting rust-rustls-webpki package, versions *


Severity

Recommended
0.0
low
0
10

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Threat Intelligence

EPSS
0.18% (9th percentile)

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  • Snyk IDSNYK-ECHOLATEST-RUSTRUSTLSWEBPKI-19946246
  • published19 Sept 2026
  • disclosed18 Sept 2026

Introduced: 18 Sep 2026

NewCVE-2026-93601  (opens in a new tab)
CWE-295  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest rust-rustls-webpki.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rust-rustls-webpki package and not the rust-rustls-webpki package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

rustls-webpki (the Rust webpki fork used by rustls) versions >= 0.101.0 and prior to 0.103.12 and 0.104.0-alpha.6 incorrectly accepted permitted-subtree DNS name constraints for certificates asserting a wildcard name. For example, a name constraint of accept.example.com was treated as satisfied by a certificate for *.example.com, which could feasibly assert reject.example.com — a name outside the permitted subtree. Because name constraints are restrictions applied to otherwise properly issued certificates, the issue is only reachable after signature verification succeeds and requires a misissued wildcard certificate to exploit.

CVSS Base Scores

version 3.1