CVE-2025-59432 identifies a timing attack vulnerability in the SCRAM (Salted Challenge Response Authentication Mechanism) Java implementation provided by the ongres scram library prior to version 3.2. SCRAM is a SASL authentication mechanism widely used to securely authenticate clients and servers. The vulnerability stems from the use of the Java method Arrays.equals to compare secret values such as client proofs and server signatures during the authentication process. Arrays.equals performs a byte-by-byte comparison but short-circuits upon the first mismatch, causing the execution time to vary based on how many initial bytes match. This timing discrepancy can be measured by an attacker to gradually infer secret authentication material, potentially compromising the authentication process. The vulnerability is classified under CWE-208 (Observable Timing Discrepancy) and CWE-385 (Use of Short Circuiting). The issue was addressed in version 3.2 of ongres scram by replacing Arrays.equals with MessageDigest.isEqual, which performs constant-time comparisons, mitigating timing side-channel leaks. The CVSS 4.0 base score is 6.6, reflecting a medium severity with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality. No known exploits have been reported in the wild as of the publication date (September 22, 2025).

For European organizations, this vulnerability poses a moderate risk to the confidentiality of authentication credentials when using SCRAM via the ongres scram Java library versions prior to 3.2. Successful exploitation could allow attackers to recover sensitive authentication secrets, potentially enabling unauthorized access to systems relying on SCRAM authentication. This could lead to account compromise, lateral movement, and data breaches. The vulnerability does not affect integrity or availability directly but undermines the trustworthiness of the authentication process. Organizations using PostgreSQL or other services that integrate ongres scram for SCRAM authentication are particularly at risk. Given the medium CVSS score and lack of required privileges or user interaction, remote exploitation is feasible, increasing the threat surface. However, the absence of known exploits in the wild suggests limited active targeting currently. Still, the vulnerability should be considered a significant concern for sectors with high security requirements such as finance, government, and critical infrastructure in Europe.

European organizations should immediately assess their use of the ongres scram library for SCRAM authentication and identify any deployments running versions prior to 3.2. The primary mitigation is to upgrade to version 3.2 or later, which replaces the vulnerable Arrays.equals method with a constant-time comparison function (MessageDigest.isEqual). Where immediate upgrade is not feasible, organizations should consider additional network-level protections such as restricting access to authentication endpoints, implementing rate limiting to reduce timing attack feasibility, and monitoring authentication logs for anomalous access patterns. Developers should audit any custom SCRAM implementations to ensure constant-time comparison methods are used for secret data. Security teams should also educate developers and administrators about timing side-channel risks and incorporate side-channel resistant coding practices in authentication modules. Finally, organizations should stay alert for any emerging exploit tools targeting this vulnerability and apply patches promptly.