CVE-2020-27386
An unrestricted file upload issue in FlexDotnetCMS before v1.5.9 allows an authenticated remote attacker to upload and execute arbitrary files by using the FileManager to upload malicious code (e.g., ASP code) in the form of a safe file type (e.g., a TXT file), and then using the FileEditor (in v1.5.8 and prior) or the FileManager's rename function (in v1.5.7 and prior) to rename the file to an executable extension (e.g., ASP), and finally executing the file via an HTTP GET request to /<path_to_file>.
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 77.95% probability of being exploited in the next 30 days, ranking higher than 99% of all scored CVEs.
Related Vulnerabilities
Similar SeverityHIGH
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OpenClaw before 2026.4.22 contains an exec allowlist analysis vulnerability allowing shell expansion hiding in unquoted heredoc bodies. Attackers can bypass allowlist validation by embedding shell expansion tokens in heredoc bodies to execute unapproved commands at runtime.
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