CVE-2009-3875: The MessageDigest.isEqual function in Java Runtime Environment (JRE) in Sun Java SE in JDK and JRE 5.0 befo...

Security readout for executives and security teams

CVE-2009-3875 affects old Sun Java runtimes. A timing weakness in MessageDigest.isEqual could let a remote attacker spoof HMAC-based digital signatures and possibly bypass authentication. This matters most where legacy Java verifies signed requests, tokens, or API messages. Likely exposure is limited to legacy Java deployments or embedded vendor products still running the affected versions, especially systems using HMAC signature checks for authentication or request integrity. Treat as high priority only where legacy Java remains in security-sensitive authentication paths. For modern Java estates, this is mainly an audit and cleanup item. Unsupported runtimes should be removed because this CVE indicates broader operational risk. Mitigation focus: Upgrade affected Java runtimes to the fixed update levels or later.; Apply relevant OS or vendor Java security updates from supported distributors.; Retire unsupported Java 1.3, 1.4, 5, and early 6 runtimes where possible..

Prepared

Jun 28, 2026, 18:15 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.