Vulnerability Description
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.
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-11835?
CVE-2026-11835 is a documented vulnerability. 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 ...
How severe is CVE-2026-11835?
CVSS scoring is not yet available for CVE-2026-11835. Check NVD for updates.
Is there a patch for CVE-2026-11835?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.