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TI-2020-11879 Aliases CVE-2020-15104

TLS Validation Vulnerability in Envoy

Priority LOW 24CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-346.

Summary

In Envoy before versions 1.12.6, 1.13.4, 1.14.4, and 1.15.0 when validating TLS certificates, Envoy would incorrectly allow a wildcard DNS Subject Alternative Name apply to multiple subdomains. For example, with a SAN of *.example.com, Envoy would incorrectly allow nested.subdomain.example.com, when it should only allow subdomain.example.com. This defect applies to both validating a client TLS certificate in mTLS, and validating a server TLS certificate for upstream connections. This vulnerability is only applicable to situations where an untrusted entity can obtain a signed wildcard TLS certificate for a domain of which you only intend to trust a subdomain of. For example, if you intend to trust api.mysubdomain.example.com, and an untrusted actor can obtain a signed TLS certificate for *.example.com or *.com. Configurations are vulnerable if they use verify_subject_alt_name in any Envoy version, or if they use match_subject_alt_names in version 1.14 or later. This issue has been fixed in Envoy versions 1.12.6, 1.13.4, 1.14.4, 1.15.0.

Why it matters now

EPSS 0.00252 16th percentileScored 2026-11-07
Fix Fixed envoy (envoyproxy): 1.12.6, 1.13.4, 1.14.4Red Hat: 1 advisory

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
envoyproxyenvoybefore 1.12.6; 1.13.0 to before 1.13.4; 1.14.0 to before 1.14.41.12.6, 1.13.4, 1.14.4Patch availableCNA
  • envoy Vendorenvoyproxy Affected before 1.12.6; 1.13.0 to before 1.13.4; 1.14.0 to before 1.14.4 Fixed in 1.12.6, 1.13.4, 1.14.4 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*before 1.12.6; 1.13.0 to before 1.13.4; 1.14.0 to before 1.14.4Vulnerableenvoyproxy
  • cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* Versions before 1.12.6; 1.13.0 to before 1.13.4; 1.14.0 to before 1.14.4 Vulnerable ·envoyproxy

Remediation

  • Fix · CNA envoy (envoyproxy) Fixed in 1.12.6, 1.13.4, 1.14.4

Red Hat 1 advisory

  • RHSA-2020:3090 Released 2020-07-22 · Red Hat rating Moderate
    Red Hat OpenShift Service Mesh 1.1 servicemesh-proxy security update
    • OpenShift Service Mesh 1.1 servicemesh-proxy-1.1.5-1.el8

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
OpenShift Service Mesh 1.1Fixed RHSA-2020:3090

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-15104

References

Advisory 1

  • TI-2026-79288 Out-of-bounds write in Google Brotli decoder KEVCVSS 4.0CRITICAL 9.2
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2024-20001 HTTP/2: CPU exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
  • TI-2024-18524 HTTP/2: memory exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
  • TI-2023-12215 Envoy client may fake the header `x-envoy-original-path` CVSS 3.1CRITICAL 9.1
  • TI-2023-18002 Envoy vulnerable to OAuth2 credentials exploit with permanent validity CVSS 3.1CRITICAL 9.8
See all 126 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences