Post

CVE-2026-11836 - Production Debug-Unlock Token Verification Missing Device Binding

Posted
By ictsec.pl
1 min read
CVE-2026-11836 - Production Debug-Unlock Token Verification Missing Device Binding

CVE-2026-11836: Production Debug-Unlock Token Verification Missing Device Binding

This vulnerability is rated as LOW with a CVSS score of 4.0 (1.8). Insufficient verification of data authenticity in Caliptra Core ROM and Core Firmware (validate_debug_unlock_token()) in subsystem mode allows an attacker with access to the integrator’s debug unlock signing service to unlock production debug on an unintended device by presenting a valid token issued for a different device sharing the same debug unlock key hash.

The 384-bit challenge nonce continues to prevent replay of previously issued tokens. Practical impact is limited to loss of per-device scope enforcement within a set of devices that share the same unlock authority by design; it does not enable debug unlock on devices outside that set. This issue affects:

  • Core ROM: 2.0.0 through 2.0.2, 2.1.0 through 2.1.1
  • Core Firmware: 2.0.0 through 2.0.1, 2.1.0

Recommendations

To address this, implement stricter validation for debug unlock tokens to enforce per-device scope. Solutions include:

  • Updating Caliptra Core ROM and Core Firmware
  • Verifying debug unlock token authenticity and scope
  • Ensuring unique tokens for each device
  • Restricting access to the debug unlock signing service

CVE-2026-11836 is associated with the following CWE: CWE-345: Insufficient Verification of Data Authenticity. Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-11836 weaknesses. These include:

  • CAPEC-111: JSON Hijacking (aka JavaScript Hijacking)
  • CAPEC-141: Cache Poisoning
  • CAPEC-142: DNS Cache Poisoning
  • CAPEC-148: Content Spoofing
  • CAPEC-218: Spoofing of UDDI/ebXML Messages
  • CAPEC-384: Application API Message Manipulation via Man-in-the-Middle
  • CAPEC-385: Transaction or Event Tampering via Application API Manipulation
  • CAPEC-386: Application API Navigation Remapping
  • CAPEC-387: Navigation Remapping To Propagate Malicious Content

For more details, please read the complete article: Read full article 🚀

SECURITY
CVE VULNERABILITY DEBUG TOKEN SECURITY
This post is licensed under CC BY 4.0 by the author.