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TI-2026-10213 Aliases CVE-2026-11835

Caliptra Update-Reset Secure-Boot Bypass via Attacker-Chosen AXI Staging Address (TOCTOU)

Priority LOW 24CWE-20Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00108 1st percentileScored 2026-11-07
Fix Fixed Core ROM (Caliptra): 2.1.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CaliptraCore ROM2.1.0 – 2.1.12.1.2Patch availableCNA
  • Core ROM VendorCaliptra Affected 2.1.0 – 2.1.1 Fixed in 2.1.2 Patch available CNA

Remediation

  • Fix · CNA Core ROM (Caliptra) Fixed in 2.1.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-11835

References

Other 1

  • TI-2026-05099 MCU Firmware Update Authentication Bypass on Caliptra Core CVSS 4.0HIGH 7.2
  • TI-2026-06435 Unverified AXI Address in Subsystem Mode Commands Enables Denial of Service CVSS 4.0MEDIUM 6.8
  • TI-2026-05666 AES-256-GCM Authentication Tag Does Not Cover First Ciphertext Blocks When AAD Is Empty CVSS 4.0MEDIUM 5.1
  • TI-2026-10214 Production Debug-Unlock Token Verification Missing Device Binding CVSS 4.0LOW 1.8

Sources

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