Executive brief
Entrust nShield hardware security modules (HSMs) are devices that manage cryptographic keys and perform security-critical operations for enterprises. An attacker with physical access to these devices can modify the GRUB bootloader configuration to execute a root shell at startup, gaining complete control of the HSM and compromising all cryptographic operations and stored keys. This vulnerability puts enterprise cryptographic infrastructure at severe risk if the device is accessible to unauthorized personnel.
Technical details
This vulnerability stems from improper privilege management in the boot chain protection of nShield HSM devices. An attacker with physical proximity and high privileges (administrative access to the device or ability to modify bootloader configurations) can edit the Legacy GRUB bootloader configuration to execute arbitrary commands with root privileges during system boot. The attack does not require network access (physical attack vector only) and does not require user interaction once bootloader access is obtained. Successful exploitation grants the attacker root-level control over the HSM, enabling compromise of cryptographic operations, key theft, and persistent backdoors. Patches are available in version 13.6.12 (LTS) and 13.9.0 (STS); versions through 13.6.11 and 13.7 are affected.
Affected products
- Entrust nShield Connect XC through 13.6.11, or 13.7 (patched in 13.6.12 LTS and 13.9.0 STS)
- Entrust nShield 5c through 13.6.11, or 13.7 (patched in 13.6.12 LTS and 13.9.0 STS)
- Entrust nShield HSMi through 13.6.11, or 13.7 (patched in 13.6.12 LTS and 13.9.0 STS)
Timeline
- 2025-09-22: disclosed: Google security research disclosed multiple vulnerabilities including F06
- 2025-12-02: advisory: CVE-2025-59697 published by NVD
- 2025: patched: Patched in 13.6.12 (LTS) and 13.9.0 (STS)