Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-81829

Gravedad CVSS v3.1:
MEDIA
Tipo:
CWE-22 Limitación incorrecta de nombre de ruta a un directorio restringido (Path Traversal)
Fecha de publicación:
17/09/2026
Última modificación:
21/09/2026

Descripción

*** Pendiente de traducción *** A flaw was found in SmallRye JWT's AwsAlbKeyResolver, which is used by applications to verify JSON Web Tokens signed by AWS Application Load Balancers. When the AWS_ALB key provider is configured, the resolver constructs the key-fetch URL by directly concatenating the attacker-controlled kid header value from an inbound JWT without sanitizing path traversal characters or query-string separators. This allows an unauthenticated remote attacker to force the application server to issue GET requests to arbitrary paths on the same origin as the configured key endpoint. As a result, non-public endpoints or internal data reachable on that origin may be read by the attacker before JWT signature verification takes place.