Security readout for executives and security teams
Plain-English summary
CVE-2021-22716 affects Schneider Electric C-Bus Toolkit V1.15.9 and prior. A low-privileged local user could modify a critical file and potentially achieve code execution, creating serious confidentiality, integrity, and availability risk on affected systems.
Executive priority
Prioritize remediation for environments where C-Bus Toolkit is used on shared workstations, engineering systems, or operational technology support hosts. The impact can be high, but exploitation requires local low-privileged access based on the provided evidence.
Technical view
The issue is CWE-732, incorrect permission assignment for a critical resource. The CVSS 3.1 vector is AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H, score 7.8. The source bundle identifies C-Bus Toolkit V1.15.9 and prior as affected.
Likely exposure
Exposure is most likely on workstations or systems where Schneider Electric C-Bus Toolkit V1.15.9 or earlier is installed and local unprivileged users can access or modify Toolkit-related files.
Exploitation context
The CVSS vector indicates local access and low privileges are required. The provided sources do not indicate CISA KEV listing or active exploitation. Treat this as a serious local privilege-to-code-execution risk, not confirmed internet-scale exploitation.
Researcher notes
The public bundle supports high impact but does not include exploit details, observed exploitation, or a named fixed version. Research should focus on permission boundaries, local user write paths, and vendor advisory guidance without assuming remote network exploitability.
Mitigation direction
- Inventory all C-Bus Toolkit installations and identify versions V1.15.9 or earlier.
- Check Schneider Electric advisory SEVD-2021-103-01 for vendor-approved updates or mitigations.
- Restrict unprivileged local write access to Toolkit installation and configuration paths.
- Limit interactive access to systems running the Toolkit until remediated.
- Monitor affected hosts for unexpected changes to Toolkit-related files.
Validation and detection
- Confirm installed C-Bus Toolkit version on each relevant host.
- Review filesystem permissions for Toolkit files and directories.
- Verify unprivileged users cannot modify critical Toolkit resources.
- Check remediation status against Schneider Electric and CISA advisory guidance.
- Record compensating controls where vendor remediation is not yet applied.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-732: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-22716 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-103-01&p_enDocType=Security+and+Safety+Notice&p_File_Name=SEVD-2021-103-01_C-Bus_Toolkit_C-Gate_Server_Security_Notification.pdfCVE reference
- https://us-cert.cisa.gov/ics/advisories/icsa-21-105-01CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Incorrect Permission Assignment for Critical Resource
Incorrect Permission Assignment for Critical Resource represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.