Description

CPSD CryptoPro Secure Disk for Bitlocker before v7.7.4 stores TPM2.0 secrets in a serialized format within unused disk sectors. An unauthenticated attacker with physical access to the system disk can recover this information and craft an environment to unseal the TPM.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.6",
  "pubDate": "2026-08-12T15:17:29.787Z",
  "pubdate": "2026-08-12T15:17:29.787Z",
  "executiveSummary": "A physical security vulnerability exists in CPSD CryptoPro Secure Disk for Bitlocker before v7.7.4, involving insecure plaintext or weak serialization storage of TPM2.0 secrets.\nThe vulnerability allows an unauthenticated physical attacker to extract sensitive cryptographic material stored within unused disk sectors.\nSuccessful exploitation enables the adversary to recover the serialized secrets and construct a tailored execution environment capable of unsealing the Trusted Platform Module.\nThis undermines the hardware-backed root of trust established by the TPM for full disk encryption, exposing sensitive data at rest to unauthorized actors with physical access.\nThe risk implication is critical for systems utilizing affected versions of the software in environments where physical security cannot be guaranteed, such as mobile workstations or unattended endpoints.\nMitigation requires updating the affected product to the patched version or implementing compensating hardware security controls.",
  "technicalDetails": "The root cause of the vulnerability resides in the cryptographic implementation and key management routines of CPSD CryptoPro Secure Disk for Bitlocker before v7.7.4.\nSpecifically, the software serializes TPM2.0 secrets and persists this critical cryptographic data directly into unused or unallocated sectors of the system disk rather than relying exclusively on secure, non-volatile platform storage or protected NVRAM indices.\nBecause the secret material is written to standard disk sectors in a predictable or recoverable serialized format, it remains accessible to low-level disk read operations.\nThe attack flow requires an unauthenticated adversary to obtain physical access to the target system disk. The attacker extracts the storage medium or boots the hardware into a controlled pre-boot execution environment or alternate operating system.\nOnce physical access is established, the attacker scans the unused disk sectors to locate the serialized TPM2.0 secrets. Upon recovering the serialized data structures, the adversary parses the payload to extract the authorization values or sealing keys.\nIn the post-exploitation phase, the attacker crafts a specialized execution environment that emulates or leverages the recovered parameters to unseal the TPM, thereby bypassing the intended hardware-based access controls protecting the Bitlocker encrypted volumes.\nAuthentication requirements are none, as the attack leverages direct physical access to the storage media, bypassing logical operating system authentication layers.\nPrivilege requirements are limited to physical access capabilities sufficient to extract the disk or read raw sector data.\nNetwork exposure is non-existent, as the vulnerability is entirely physical and local to the storage device.\nThe affected component is the secret management and storage subsystem of CPSD CryptoPro Secure Disk for Bitlocker in versions prior to v7.7.4."
}