Cyber Resilience

CVE-2021-21428

CriticalPublic PoCLPE

Published: 10 May 2021

Published
10 May 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.3 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0005 16.0th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21428 is a critical-severity Improper Privilege Management (CWE-269) vulnerability in Openapi-Generator Openapi Generator. Its CVSS base score is 9.3 (Critical).

Operationally, ranked at the 16.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Openapi generator is a java tool which allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec. openapi-generator-online creates insecure temporary folders with File.createTempFile during the code generation process. The insecure temporary…

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folders store the auto-generated files which can be read and appended to by any users on the system. The issue has been patched with `Files.createTempFile` and released in the v5.1.0 stable version.

CWE(s)

Related Threats

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

Affected Assets

openapi-generator
openapi generator
≤ 5.1.0

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-269 CWE-668

Terminating and reviewing connections manages privileges associated with internal interfaces.

addresses: CWE-269 CWE-668

The control enforces proper privilege boundaries by ensuring user functionality cannot invoke or manage system-level privileges.

addresses: CWE-269 CWE-668

Separate execution domains enforce privilege boundaries so that improper privilege management within one process cannot affect others.

addresses: CWE-269

Policy addresses roles, responsibilities, and privilege management to prevent improper privilege assignments.

addresses: CWE-269

Access supervision ensures privileges are assigned and managed without improper escalation or retention.

addresses: CWE-269

Assigning group/role memberships and access authorizations (privileges) while reviewing accounts addresses improper privilege management.

addresses: CWE-668

Controls whether organization resources are exposed to external system spheres by permitting or prohibiting their use.

addresses: CWE-668

The control ensures information is not released into a security sphere where the recipient lacks matching access authorizations.

References