Answer in brief
CVE-2026-93601 records a Unknown severity vulnerability in rustls webpki 0.101.0 before 0.103.12 Name Constraint Bypass. The current sources do not mark it as known exploited. The current feed maps rustls/webpki (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps rustls/webpki (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| rustls/webpkigeneric | >=0.101.0 <0.103.12 || >=0.104.0-alpha.1 <0.104.0-alpha.6 | 0.103.12, 0.104.0-alpha.6 |
Published upstream
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 18, 2026
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.
Quoted source text, attributed separately from HOL analysis.