CVE WatchOct 30, 2026

CVE-2026-59396

A denial-of-service vulnerability exists in UAA's private_key_jwt client-authentication mechanism. When UAA retrieves a remote JWKS URI, it

CVSS

4.9

Medium

EPSS

0.3%

p21

KEV

—

Exploit Today

0-100

Published: Oct 30, 2026 · Last modified: Oct 30, 2026 · CWE-400

EPSS · 30d

0.3%EPSS · 30 days0.3%

2026-10-302026-11-07

Technical description

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.

Official references

www.cloudfoundry.orghttps://www.cloudfoundry.org/blog/cve-2026-59396-dos-vulnerability-in-uaa-related-to-jwks-uri-handling-2/

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