Cyber Resilience

CVE-2023-20903

Medium

Published: 28 March 2023

Published
28 March 2023
Modified
19 February 2025
KEV Added
Patch
CVSS Score v3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0016 36.4th percentile
Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-20903 is a medium-severity Insufficient Session Expiration (CWE-613) vulnerability in Cloudfoundry User Account And Authentication. Its CVSS base score is 4.3 (Medium).

Operationally, ranked at the 36.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

This disclosure regards a vulnerability related to UAA refresh tokens and external identity providers.Assuming that an external identity provider is linked to the UAA, a refresh token is issued to a client on behalf of a user from that identity…

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provider, the administrator of the UAA deactivates the identity provider from the UAA. It is expected that the UAA would reject a refresh token during a refresh token grant, but it does not (hence the vulnerability). It will continue to issue access tokens to request presenting such refresh tokens, as if the identity provider was still active. As a result, clients with refresh tokens issued through the deactivated identity provider would still have access to Cloud Foundry resources until their refresh token expires (which defaults to 30 days).

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

cloudfoundry
user account and authentication
all versions

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-613

Locks the device (typically after inactivity) until re-authentication, addressing insufficient session expiration by preventing indefinite access.

addresses: CWE-613

Automatically terminating sessions after a defined period directly enforces session expiration, preventing indefinite session lifetimes that attackers can exploit.

addresses: CWE-613

Re-authentication after inactivity or time-based triggers prevents indefinite use of potentially hijacked or stale sessions.

addresses: CWE-613

Terminating sessions and network connections upon completion prevents insufficient session expiration.

addresses: CWE-613

Directly enforces termination of network sessions after inactivity or end-of-session, preventing indefinite session lifetime.

addresses: CWE-613

Consistent clocks across systems allow session expiration and timeout enforcement to function as intended in distributed environments.

addresses: CWE-613

When the non-persistent artifact is a session or connection, mandatory termination implements the missing expiration that CWE-613 describes.

addresses: CWE-613

Timed refresh of session-related information or on-demand generation plus deletion implements proper session expiration.

References