Cyber Resilience

CVE-2021-21911

HighPublic PoCLPE

Published: 22 December 2021

Published
22 December 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0004 11.6th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21911 is a high-severity Incorrect Default Permissions (CWE-276) vulnerability in Advantech R-Seenet. Its CVSS base score is 7.8 (High).

Operationally, ranked at the 11.6th 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

A privilege escalation vulnerability exists in the Windows version of installation for Advantech R-SeeNet Advantech R-SeeNet 2.4.15 (30.07.2021). A specially-crafted file can be replaced in the system to escalate privileges to NT SYSTEM authority. An attacker can provide a malicious…

more

file to trigger this vulnerability.

CWE(s)

Related Threats

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

Affected Assets

advantech
r-seenet
2.4.15

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-276

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

addresses: CWE-269 CWE-276

Implements core proper privilege management by restricting to only required rights.

addresses: CWE-269 CWE-276

Baseline configuration documents and controls privilege assignments, making improper privilege management harder to introduce or sustain.

addresses: CWE-276 CWE-269

Requiring the most restrictive settings instead of defaults prevents incorrect default permissions on resources.

addresses: CWE-269 CWE-276

Defines roles and responsibilities to ensure proper privilege management during configuration changes.

addresses: CWE-269 CWE-276

Designates roles and review processes for managing physical privileges and access rights.

addresses: CWE-276 CWE-269

Tailoring explicitly overrides or scopes default permission assignments in the baseline to match the system's actual risk and operational needs.

addresses: CWE-269 CWE-276

Centralized privilege assignment and oversight prevent ad-hoc or excessive privilege grants that occur when each system is configured independently.

References