CVE-2021-27661
Published: 01 July 2021
Summary
CVE-2021-27661 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Johnsoncontrols F4-Snc Firmware. Its CVSS base score is 8.8 (High).
Operationally, ranked at the 40.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-14407
Vulnerability details
Successful exploitation of this vulnerability could give an authenticated Facility Explorer SNC Series Supervisory Controller (F4-SNC) user an unintended level of access to the controller’s file system, allowing them to access or modify system files by sending specifically crafted web…
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messages to the F4-SNC.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
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.
Policy addresses roles, responsibilities, and privilege management to prevent improper privilege assignments.
Access supervision ensures privileges are assigned and managed without improper escalation or retention.
Assigning group/role memberships and access authorizations (privileges) while reviewing accounts addresses improper privilege management.
The small, testable reference monitor reduces the likelihood of incorrect authorization implementations.
Certification evaluates whether authorization decisions are correctly implemented and enforced.
Periodic review and documentation of connection needs reduces incorrect authorization.
Restricting who can perform changes helps ensure privileges are managed properly rather than assigned broadly.
Manages privileges by authorizing only approved personnel and supervising those lacking required authorizations for maintenance.