CVE-2025-54981 is a cryptographic vulnerability identified in Apache StreamPark, an open-source real-time data processing platform maintained by the Apache Software Foundation. The vulnerability stems from the use of the AES cipher in ECB (Electronic Codebook) mode, which is widely recognized as insecure because it encrypts identical plaintext blocks into identical ciphertext blocks, enabling pattern leakage. Additionally, the implementation uses a weak random number generator to encrypt sensitive data, including JSON Web Tokens (JWTs) used for authentication. This combination significantly weakens the confidentiality guarantees of the encryption, potentially allowing remote attackers to recover sensitive authentication tokens or other confidential data without requiring any privileges or user interaction. The affected versions range from 2.0.0 up to but not including 2.1.7, where the issue has been fixed by adopting stronger cryptographic practices. The CVSS v3.1 base score of 7.5 reflects the vulnerability's high confidentiality impact, with no impact on integrity or availability, and the ease of remote exploitation without authentication. Although no known exploits are currently reported in the wild, the vulnerability poses a serious risk to any deployment handling sensitive authentication data. The weakness is categorized under CWE-327, which covers the use of broken or risky cryptographic algorithms. The Apache Software Foundation recommends immediate upgrading to version 2.1.7 to mitigate this risk.

For European organizations, this vulnerability presents a significant risk to the confidentiality of sensitive authentication data, such as JWT tokens, potentially leading to unauthorized access if attackers can decrypt or manipulate encrypted tokens. This could result in account compromise, unauthorized data access, and lateral movement within networks. Organizations relying on Apache StreamPark for real-time data processing, especially in sectors like finance, telecommunications, and critical infrastructure, could face data breaches or regulatory non-compliance under GDPR due to exposure of personal data. The lack of integrity and availability impact means systems may continue operating normally while confidentiality is compromised, making detection harder. The vulnerability's remote exploitability without authentication increases the attack surface, especially for internet-facing deployments. Although no exploits are known in the wild yet, the widespread use of Apache StreamPark in European enterprises and public sector entities elevates the urgency of remediation to prevent potential exploitation.

The primary mitigation is to upgrade Apache StreamPark to version 2.1.7 or later, where the cryptographic implementation has been corrected to use secure cipher modes and robust random number generators. Organizations should audit their current deployments to identify affected versions and prioritize patching. Additionally, review all cryptographic configurations and implementations related to authentication tokens to ensure they use secure algorithms such as AES in GCM or CBC mode with proper IV management, and cryptographically secure random number generators. Implement network segmentation and monitoring to detect anomalous access patterns that could indicate exploitation attempts. Employ token expiration and rotation policies to limit the window of exposure if tokens are compromised. Finally, conduct security awareness training for developers and administrators on secure cryptographic practices to prevent recurrence.