CVE-2021-4314

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-01-18 · updated 2026-06-17
Weakness: CWE-269

Description

It is possible to manipulate the JWT token without the knowledge of the JWT secret and authenticate without valid JWT token as any user. This is happening only in the situation when zOSMF doesn’t have the APAR PH12143 applied. This issue affects: 1.16 versions to 1.19. What happens is that the services using the ZAAS client or the API ML API to query will be deceived into believing the information in the JWT token is valid when it isn’t. It’s possible to use this to persuade the southbound service that different user is authenticated.

Affected products

Open Mainframe Project Zowe: from 1.16.0 before 1.19.0 — fixed in 1.19.0

How to fix

Upgrade to a fixed version: Open Mainframe Project Zowe 1.19.0. Check the vendor advisory for mitigations.

References

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