CVE-2025-13353 is a cryptographic vulnerability in Cloudflare's gokey utility, specifically in versions before 0.2.0. The flaw arises from a bug in the seed decryption logic where passwords and secrets derived using the '-s' option (seed file as entropy input) were generated using only 28 bytes of entropy instead of the expected 240 bytes. This insufficient randomness stems from deriving keys solely from the AES-GCM initialization vector and authentication tag of the seed, ignoring the full seed entropy. Consequently, an attacker with access to the seed file could recover all passwords generated from that seed without needing the master password, compromising confidentiality. Keys generated without the seed file (i.e., from the master password alone) remain unaffected. The vulnerability was responsibly disclosed and fixed in gokey version 0.2.0, which employs a corrected key derivation process utilizing the entire seed entropy, resulting in different secrets even from the same seed file. Due to this deterministic change, all secrets generated with vulnerable versions must be regenerated and rotated. The CVSS 4.0 vector indicates local attack vector, low attack complexity, partial privileges required, no user interaction, and high impact on confidentiality. No known exploits are currently in the wild. The vulnerability primarily affects environments where gokey is used with seed files for secret generation, such as automated credential provisioning and cryptographic key management.

For European organizations, the impact of CVE-2025-13353 is significant in environments relying on gokey for generating cryptographic keys and passwords using seed files. The reduced entropy in generated secrets means that if an attacker gains access to the seed file, they can potentially recover all derived secrets without needing the master password, leading to a full compromise of credentials and sensitive systems. This undermines the confidentiality and integrity of authentication mechanisms, potentially allowing unauthorized access to critical infrastructure, internal services, or cloud environments. The deterministic nature of the fix means that all affected secrets must be rotated, which could be operationally challenging and resource-intensive. Organizations using gokey in automated pipelines or for SSH key generation may face increased risk of lateral movement or privilege escalation if old secrets remain active. The vulnerability does not affect secrets generated without seed files, limiting the scope somewhat. However, the breach of seed-based secrets could lead to cascading security failures, especially in sectors with high security requirements such as finance, government, and critical infrastructure within Europe.

1. Immediately upgrade all gokey installations to version 0.2.0 or later to apply the fix that correctly uses full seed entropy in key derivation. 2. Identify all secrets and passwords generated using gokey with the '-s' seed file option and regenerate them using the patched version. 3. Implement a comprehensive secret rotation plan tailored to each system type: use 'forgot password' flows where available, or recover old secrets with gokey 0.1.3 if required for rotation. 4. For systems allowing multiple credentials (e.g., SSH), provision new keys alongside old ones, verify access, then revoke old keys to avoid downtime. 5. Secure and restrict access to seed files to prevent unauthorized possession, as possession alone enables secret recovery in vulnerable versions. 6. Audit and monitor systems for unauthorized access attempts potentially exploiting compromised secrets. 7. Educate security teams and developers on the implications of using seed files with gokey and encourage use of master-password-only generation where feasible. 8. Review and harden operational procedures around secret management to minimize exposure and improve incident response readiness.