CVE-2026-59396

MediumCVSS 4.9

Published: 30/10/2026(UTC)Updated: 30/10/2026(UTC)Translated: 30/10/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.29%

21th percentile - higher than 21% of all known CVEs

Summary

A denial-of-service vulnerability exists in UAA's private_key_jwt client-authentication mechanism. When UAA retrieves a remote JWKS URI, it caches the response, and invalid authentication attempts can trigger full deserialization of this cached data.

Risk Assessment

An attacker with prerequisites (write access to clients or a compromised endpoint) can send anonymous requests that force repeated parsing of large cached objects, causing excessive CPU usage and potential Java heap exhaustion via OutOfMemoryError, resulting in service unavailability.

Recommendation

Upgrade UAA to a version containing the fix for this vulnerability. Restrict write access to client configuration and secure remote JWKS endpoints against compromise.

Other vulnerabilities in UAA

CVE-2026-47840High
A network attacker positioned between UAA and its LDAP directory can impersonate the directory using any certificate from any trusted CA, then harvest the LDAP bind password and every end-user password sent during simple-bind authentication, and return forged group memberships that grant themselves admin scopes.

Original NVD description (English source)

A denial-of-service vulnerability exists in UAA's private_key_jwt client-authentication mechanism. When UAA retrieves a remote JWKS URI, it caches the response. Invalid authentication attempts can trigger full deserialization of this cached data. An attacker with prerequisites (write access to clients or a compromised endpoint) can send anonymous requests that force repeated parsing of large cached objects, causing excessive CPU usage and potential Java heap exhaustion via OutOfMemoryError, resulting in service unavailability.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS