CVE-2024-28285: Crypto++ Privilege Escalation Vulnerability

CVE-2024-28285 Overview

A Fault Injection vulnerability has been identified in the SymmetricDecrypt function within cryptopp/elgamal.h of Cryptopp Crypto++ version 8.9. This vulnerability allows an attacker who can co-reside in the same system with a victim process to disclose sensitive information and escalate privileges. The flaw represents a significant side-channel attack vector that undermines the cryptographic security guarantees of the ElGamal encryption implementation.

Critical Impact

Attackers with local system access can exploit fault injection techniques to extract sensitive cryptographic material and escalate privileges, potentially compromising encrypted communications and system security.

Affected Products

• Cryptopp Crypto++ 8.9
• Applications utilizing the ElGamal implementation in cryptopp/elgamal.h
• Systems where attackers can achieve co-residency with victim processes

Discovery Timeline

• 2024-05-14 - CVE-2024-28285 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-28285

Vulnerability Analysis

This vulnerability belongs to the category of Side Channel Attack vulnerabilities, specifically targeting the ElGamal cryptographic implementation through fault injection techniques. The flaw exists in the SymmetricDecrypt function, where improper handling of computational faults during decryption operations can leak sensitive information about the private key or plaintext data.

Fault injection attacks exploit the physical or software-based manipulation of computational processes to induce errors that reveal information about internal cryptographic state. In this case, an attacker co-residing on the same physical or virtual system can introduce controlled faults during ElGamal decryption operations. By analyzing the resulting erroneous outputs or timing differences, the attacker can progressively extract the private key material.

The vulnerability is classified under CWE-209 (Generation of Error Message Containing Sensitive Information), indicating that error conditions or fault responses may inadvertently expose cryptographic secrets. The attack requires the adversary to have local system access or the ability to influence the execution environment of the victim process.

Root Cause

The root cause lies in the SymmetricDecrypt function's failure to adequately protect against fault-based side-channel attacks. The implementation does not incorporate sufficient countermeasures such as algorithmic blinding, redundant computations, or fault detection mechanisms that would prevent information leakage when computational errors occur during decryption operations.

Attack Vector

The attack exploits the network-accessible nature of applications using the vulnerable Crypto++ library. An attacker must first achieve co-residency with the target process, which can occur in cloud computing environments, shared hosting scenarios, or through malware execution on the target system. Once co-located, the attacker can:

1. Induce controlled faults through voltage glitching, clock manipulation, or software-based fault injection
2. Observe the decryption process responses to faulty inputs
3. Correlate fault outputs with mathematical properties of the ElGamal algorithm
4. Progressively recover the private key through differential fault analysis

A proof-of-concept demonstrating this vulnerability is available through the GitHub Gist PoC.

Detection Methods for CVE-2024-28285

Indicators of Compromise

• Unusual computational patterns or timing anomalies in cryptographic operations
• Repeated decryption failures or error messages from Crypto++ ElGamal functions
• Evidence of co-resident processes with elevated privileges or suspicious behavior
• Anomalous system events indicating potential fault injection attempts (voltage fluctuations, clock irregularities)

Detection Strategies

• Monitor for applications using Crypto++ version 8.9 with ElGamal encryption functionality
• Implement runtime integrity monitoring for cryptographic library operations
• Deploy behavioral analysis to detect abnormal decryption patterns or error rates
• Use SentinelOne's real-time process monitoring to identify suspicious co-resident processes

Monitoring Recommendations

• Enable comprehensive logging for all cryptographic operations in affected applications
• Monitor system-level events that may indicate physical or software fault injection attempts
• Implement alerting for elevated decryption failure rates or unusual error patterns
• Track process co-residency and resource sharing in virtualized or cloud environments

How to Mitigate CVE-2024-28285

Immediate Actions Required

• Audit all systems for the presence of Crypto++ 8.9 and applications utilizing the ElGamal implementation
• Evaluate the risk exposure based on the deployment environment (higher risk in shared/cloud infrastructure)
• Consider migrating to alternative cryptographic implementations with fault injection countermeasures
• Implement additional isolation measures for sensitive cryptographic processes

Patch Information

As of the last CVE update on 2024-11-21, users should monitor the official Crypto++ project for security advisories and updated releases. Review the GitHub Gist PoC for technical details on the vulnerability mechanism and potential mitigation approaches.

Workarounds

• Isolate processes using ElGamal encryption to dedicated systems where co-residency cannot be achieved
• Implement additional process isolation through containerization or virtual machine boundaries
• Consider using alternative encryption schemes that include built-in fault injection countermeasures
• Apply hardware-level protections where available, such as trusted execution environments (TEEs)

# Example: Check for vulnerable Crypto++ version
find / -name "*.h" -path "*/cryptopp/*" 2>/dev/null | xargs grep -l "elgamal" | head -5
# Review application dependencies for cryptopp version 8.9
grep -r "cryptopp" /path/to/application/dependencies/