Security readout for executives and security teams
Plain-English summary
mySCADA myDESIGNER can mishandle imported project files. A malicious project file could place or overwrite files in unintended locations, potentially leading to remote code execution. Risk is highest where engineering staff import project files from outside trusted sources.
Executive priority
Treat this as a high-priority OT engineering workstation issue, not a broad internet-facing emergency. The business concern is compromise through project file handling, which can affect engineering integrity and potentially operational availability.
Technical view
CVE-2021-43555 is a CWE-23 path traversal flaw in mySCADA myDESIGNER 8.20.0 and prior. The product fails to properly validate imported project file contents, allowing arbitrary file planting or overwrite. CVSS 3.1 is 7.3: local attack vector, low complexity, no privileges, and user interaction required.
Likely exposure
Exposure is likely limited to organizations using mySCADA myDESIGNER, especially in industrial or OT engineering environments. Systems are most exposed when users receive and import project files from vendors, contractors, email, shared drives, or other semi-trusted channels.
Exploitation context
The bundle does not cite active exploitation, and this CVE is not marked KEV. Exploitation appears to require a crafted project file and user import action. The provided sources do not establish public exploit availability or observed in-the-wild attacks.
Researcher notes
Key constraints are local vector and required user interaction. The main validation question is whether imported project archives can write outside intended directories. Avoid assuming exploit maturity; the supplied evidence only supports path traversal leading to arbitrary file write or overwrite and possible RCE.
Mitigation direction
- Identify all installations of mySCADA myDESIGNER and their versions.
- Prioritize systems running version 8.20.0 or earlier.
- Check CISA and vendor guidance for the supported fix or workaround.
- Restrict imports to trusted project files and trusted transfer paths.
- Apply least privilege to engineering workstations where feasible.
Validation and detection
- Confirm installed myDESIGNER versions across engineering endpoints.
- Review whether users import project files from external parties.
- Verify vendor-recommended updates or mitigations are applied.
- Check endpoint controls for unexpected file writes during project import workflows.
- Document compensating controls for any system that cannot be updated.
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-23: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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 lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-43555 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
- 7.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/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:N/UI:R/S:U/C:L/I:H/A:H1.85.5Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.3HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://us-cert.cisa.gov/ics/advisories/icsa-21-313-04CVE reference · x_refsource_MISC
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.
Relative Path Traversal
Relative Path Traversal represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.