CVE-2026-59276: spring spring security Observable Timing Discrepancy

Vulnerability summary

CVE-2026-59276 is a medium (CVSS 5.9) Observable Timing Discrepancy vulnerability in spring spring security. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 24.8% of scored vulnerabilities.

Timeline

1. 27-08-2026
   PublishedVulnerability first disclosed.
2. 28-08-2026
   Last modifiedVulnerability information updated.

Description

Several components in Spring Security compare security-sensitive values using standard string equality (String.equals()) rather than a constant-time comparison. Because String.equals() returns as soon as it finds a differing character, the time taken to reject an incorrect value is proportional to the number of leading characters that match the expected value. Spring Security 7.1.0 Spring Security 7.0.0 - 7.0.6 Spring Security 6.5.0 - 6.5.11 Spring Security 6.4.0 - 6.4.18 Spring Security 5.8.0 - 5.8.27 Spring Security 5.7.0 - 5.7.25

• CWE-208Observable Timing DiscrepancyTwo separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.