CVE-2026-11835

Time-of-check time-of-use (TOCTOU) vulnerability combined with missing input validation in Caliptra Core ROM (UpdateResetFlow::run()) in subsystem mode allows a compromised local attacker to silently bypass secure boot by supplying an AXI staging address that is not validated against the strap-configured SS_EXTERNAL_STAGING_AREA_BASE_ADDR, enabling firmware to be modified between verification and loading into ICCM. Attestation continues to report the originally verified image digest, masking the compromise. Exploitation requires a compromised MCU firmware with AXI manager access to unprotected SRAM reachable by Caliptra. This issue affects Core ROM: 2.1.0 through 2.1.1.

CVSS

No CVSS.

References

Link	Resource
https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-49mm-5gq5-v97f

Configurations

No configuration.

History

23 Oct 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) Vulnerabilidad de tiempo de verificación y tiempo de uso (TOCTOU) combinada con la falta de validación de entrada en la ROM del núcleo de Caliptra (UpdateResetFlow::run()) en modo de subsistema permite a un atacante local comprometido eludir silenciosamente el arranque seguro al proporcionar una dirección de preparación AXI que no se valida contra la dirección base del área de preparación externa (SS_EXTERNAL_STAGING_AREA_BASE_ADDR) configurada por correa, lo que permite que el firmware sea modificado entre la verificación y la carga en el ICCM. La atestación continúa informando el resumen de imagen verificado originalmente, enmascarando el compromiso. La explotación requiere un firmware de MCU comprometido con acceso de administrador AXI a SRAM desprotegida accesible por Caliptra. Este problema afecta a la ROM del núcleo: 2.1.0 a 2.1.1.

Information

Published : 2026-08-04 00:16

Updated : 2026-10-23 23:10

NVD link : CVE-2026-11835

Mitre link : CVE-2026-11835

CVE.ORG link : CVE-2026-11835

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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