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.
CVE-2026-93601
LOWPre-NVD 2.22.2—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 2.2 from GitHub Security Advisory (severity: LOW) published 2026-09-18. a secondary CVSS source baseline 2.2; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
2.2EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 2.2Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 2.2
- EG Score
- 2.2(high)
- EG Risk
- 10(Track)EG Risk 10/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity22% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 8%
- KEV
- Not listed
Published
September 18, 2026
Last Modified
September 18, 2026
References (2)
Vendor Advisories for CVE-2026-93601(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
crates.io(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| rustls-webpki | — | 0.103.12 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-20 20:16 UTCEPSS rescore
- 2026-09-18 18:29 UTCEG score recompute
- 2026-09-18 18:29 UTCGHSA enrichment
- 2026-09-18 17:54 UTCEG score recompute
- 2026-09-18 17:54 UTCGHSA enrichment
- 2026-09-18 14:21 UTCEG score recompute
- 2026-09-18 13:29 UTCEG score recompute
- 2026-09-18 13:29 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Same CWE
10 shownCWE-295
Frequently asked(5)
What is CVE-2026-93601?
CVE-2026-93601 is a low vulnerability published on September 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…
When was CVE-2026-93601 disclosed?
CVE-2026-93601 was first published in the National Vulnerability Database on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-93601 actively exploited?
CVE-2026-93601 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 91.9% of all scored CVEs.
What is the CVSS score of CVE-2026-93601?
CVE-2026-93601 has a CVSS v3 base score of 2.2 (NVD).
How do I remediate CVE-2026-93601?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-93601, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-93601
Is Your Infrastructure Affected by CVE-2026-93601?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.