Contour has Improper JWT Verification for Non-SNI Requests on Virtual Hosts with Fallback Certificate Enabled (CVE-2026-50149)
Contour is a Kubernetes ingress controller using Envoy proxy. In versions 1.23.0 through 1.33.4, when an `HTTPProxy` is configured with incompatible combination of both `.spec.virtualhost.tls.enableFallbackCertificate: true` and `.spec.virtualhost.jwtProviders`, Contour does not reject the configuration. Consequently, requests from clients that do not send TLS SNI or send an unrecognized SNI (one that does not match any `HTTPProxy` FQDN) bypass configured JWT verification and are proxied to upstream services without a valid token. This issue is fixed in Contour v1.33.5. Contour now rejects and marks invalid any `HTTPProxy` resources that combine `.spec.virtualhost.tls.enableFallbackCertificate: true` with `.spec.virtualhost.jwtProviders`. Affected resources will receive a status condition with the error reason `TLSIncompatibleFeatures`. As a workaround, do not enable `.spec.virtualhost.tls.enableFallbackCertificate` on `HTTPProxy` resources that also define `.spec.virtualhost.jwtProviders`. Remove one of the two settings to avoid the invalid configuration.
Contour has Improper JWT Verification for Non-SNI Requests on Virtual Hosts with Fallback Certificate Enabled (CVE-2026-50149)
Description
Contour is a Kubernetes ingress controller using Envoy proxy. In versions 1.23.0 through 1.33.4, when an `HTTPProxy` is configured with incompatible combination of both `.spec.virtualhost.tls.enableFallbackCertificate: true` and `.spec.virtualhost.jwtProviders`, Contour does not reject the configuration. Consequently, requests from clients that do not send TLS SNI or send an unrecognized SNI (one that does not match any `HTTPProxy` FQDN) bypass configured JWT verification and are proxied to upstream services without a valid token. This issue is fixed in Contour v1.33.5. Contour now rejects and marks invalid any `HTTPProxy` resources that combine `.spec.virtualhost.tls.enableFallbackCertificate: true` with `.spec.virtualhost.jwtProviders`. Affected resources will receive a status condition with the error reason `TLSIncompatibleFeatures`. As a workaround, do not enable `.spec.virtualhost.tls.enableFallbackCertificate` on `HTTPProxy` resources that also define `.spec.virtualhost.jwtProviders`. Remove one of the two settings to avoid the invalid configuration.
Affected software
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Weaknesses
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-g3xr-5w5j-w4q4
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-50149"]
- Ecosystems
- ["Go"]
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a46ecc627e9c7971943d961
Added to database: 07/02/2026, 22:57:10 UTC
Last enriched: 08/20/2026, 11:30:04 UTC
Last updated: 09/14/2026, 22:01:35 UTC
Views: 96
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