Cyber Resilience

CVE-2021-42309

HighRCE

Published: 15 December 2021

Published
15 December 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0073 73.1th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-42309 is a high-severity Code Injection (CWE-94) vulnerability in Microsoft Sharepoint Server. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 26.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Microsoft SharePoint Server Remote Code Execution Vulnerability

CWE(s)

Related Threats

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

Affected Assets

microsoft
sharepoint enterprise server
2016
microsoft
sharepoint foundation
2013
microsoft
sharepoint server
2019, 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-732 CWE-94

Overrides or renders irrelevant incorrect permission assignments on critical executable resources by using hardware-level immutability.

addresses: CWE-732

Procedures support proper permission assignment for critical resources through documented controls.

addresses: CWE-732

Attribute management for resources provides a mechanism to assign and maintain correct permissions based on security labels.

addresses: CWE-732

Prevents overly permissive assignments to critical resources by limiting to task needs.

addresses: CWE-732

Training policy covers correct permission assignment, reducing the ability to exploit incorrect permission assignments for critical resources.

addresses: CWE-732

Training on permission management reduces incorrect permission assignments for critical resources.

addresses: CWE-732

Audit logs and logging tools are critical resources whose protection requires correct permission assignments to block unauthorized actions.

addresses: CWE-732

Assessments review permission assignments on critical resources to confirm correctness, mitigating exploitation via incorrect permissions.

References