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.
https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-hw68-jjx4-m376
Published: 2026-08-04
Updated: 2026-08-04
Base Score: 3.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:N
Severity: Low
Base Score: 6.1
Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity: Medium
Base Score: 1.8
Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.0008