CVE intelligence and bounded remediation
CVE-2021-27198 — An issue was discovered in Visualware MyConnection Server before v11.1a
Critical
CVSS 9.8
An issue was discovered in Visualware MyConnection Server before v11.1a. Unauthenticated Remote Code Execution can occur via Arbitrary File Upload in the web service when using a myspeed/sf?filename= URI. This application is written in Java and is thus cross-platform. The Windows installation runs as SYSTEM, which means that exploitation gives one Administrator privileges on the target system.
- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Published
- 2021-02-26
- CISA KEV
- Not currently listed
- Ecosystem
- windows/system
- Weaknesses
- CWE-434
Affected products
- visualware / myconnection_server
Matched remediation archetype
Path traversal, unsafe upload, and file handling
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
- Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
- Review canonicalization and containment checks across supported operating systems and storage backends.
Remediate safely
- Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
- Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
- Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.
Authoritative sources
Complete CVE record and remediation plan
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