CVE-2025-14760 identifies a cryptographic vulnerability in the AWS SDK for C++ related to the handling of encrypted data keys (EDKs) used in client-side encryption with Amazon S3. Specifically, the SDK lacks cryptographic key commitment when the encrypted data key is stored in an "instruction file" instead of the standard S3 metadata record. Key commitment is a cryptographic technique that binds the ciphertext to the key, preventing substitution attacks. Without this, an attacker who has write access to the S3 bucket can replace the legitimate EDK with a malicious one that decrypts to different plaintext. This can lead to data integrity violations, as the decrypted data may be altered without detection. The vulnerability requires the attacker to have write permissions on the S3 bucket, which is a significant but not uncommon privilege in some environments. The CVSS v3.1 score is 5.3 (medium), reflecting network attack vector, high attack complexity, low privileges required, no user interaction, unchanged scope, no confidentiality impact, but high integrity impact and no availability impact. AWS addressed this issue by releasing SDK version 1.11.712, which includes the necessary cryptographic key commitment to prevent substitution of EDKs. No known exploits are reported in the wild as of the publication date. This vulnerability is categorized under CWE-327, indicating the use of a broken or risky cryptographic algorithm or practice.

For European organizations, this vulnerability poses a risk primarily to data integrity in cloud environments using the AWS SDK for C++. Organizations that implement client-side encryption with S3 and store encrypted data keys in instruction files are vulnerable if attackers gain write access to their S3 buckets. Potential impacts include unauthorized data modification, undermining trust in stored data, and possible compliance violations under regulations such as GDPR if data integrity cannot be assured. The attack does not compromise confidentiality or availability directly but can lead to corrupted or maliciously altered data being processed or consumed by applications. This risk is heightened in multi-tenant cloud environments, shared storage scenarios, or where access controls are misconfigured. The medium severity reflects that exploitation is non-trivial but feasible in environments with inadequate access controls. European organizations relying heavily on AWS cloud services for critical data storage and processing should prioritize addressing this vulnerability to maintain data integrity and regulatory compliance.

1. Upgrade the AWS SDK for C++ to version 1.11.712 or later immediately to ensure the cryptographic key commitment is enforced. 2. Audit and tighten S3 bucket permissions to restrict write access only to trusted users and services, minimizing the risk of malicious EDK injection. 3. Review application architectures to avoid storing encrypted data keys in instruction files when possible, preferring S3 metadata records which are less vulnerable. 4. Implement monitoring and alerting on S3 bucket write operations, especially for instruction files, to detect unauthorized modifications promptly. 5. Conduct regular security assessments and penetration tests focusing on cloud storage configurations and cryptographic implementations. 6. Educate development and operations teams about secure cryptographic practices and the importance of applying vendor patches promptly. 7. Consider using AWS Key Management Service (KMS) or other managed encryption services that abstract key management and reduce risks associated with manual key handling.