Summary
path traversal in Jooby
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
References
Latest 1.x version: 1.6.6
Arbitrary class path resource access 1
When sharing a File System directory as in:
assets("/static/**", Paths.get("static"));
The class path is also searched for the file (org.jooby.handlers.AssetHandler.loader):
jooby/AssetHandler.java at 1.x · jooby-project/jooby · GitHub
private static Loader loader(final Path basedir, final ClassLoader classloader) {
if (Files.exists(basedir)) {
return name -> {
Path path = basedir.resolve(name).normalize();
if (Files.exists(path) && path.startsWith(basedir)) {
try {
return path.toUri().toURL();
} catch (MalformedURLException x) {
// shh
}
}
return classloader.getResource(name);
};
}
return classloader::getResource;
}
If we send /static/WEB-INF/web.xml it will fail to load it from the file system but will go into classloader.getResource(name) where name equals /WEB-INF/web.xml so will succeed and return the requested file. This way we can get any configuration file or even the application class files
If assets are configured for a certain extension we can still bypass it. eg:
assets("/static/**/*.js", Paths.get("static"));
We can send:
http://localhost:8080/static/io/yiss/App.class.js
Arbitrary class path resource access 2
This vulnerability also affects assets configured to access resources from the root of the class path. eg:
assets("/static/**");
In this case we can traverse static by sending:
http://localhost:8080/static/..%252fio/yiss/App.class
For more information
If you have any questions or comments about this advisory:
- Open an issue in jooby
- Email us at [email protected]
Impact
Access to sensitive information available from classpath.
Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.
CVE-2020-7647 has a CVSS score of 5.3 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.8.2); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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See it in your environmentNew to Kodem? Get a demo →Remediation advice
Patched version: 1.6.7 and 2.8.2
Commit 1.x: https://github.com/jooby-project/jooby/commit/34f526028e6cd0652125baa33936ffb6a8a4a009
Commit 2.x: https://github.com/jooby-project/jooby/commit/c81479de67036993f406ccdec23990b44b0bec32
Frequently Asked Questions
- What is CVE-2020-7647? CVE-2020-7647 is a medium-severity path traversal vulnerability in io.jooby:jooby (maven), affecting versions < 2.8.2. It is fixed in 2.8.2. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
- How severe is CVE-2020-7647? CVE-2020-7647 has a CVSS score of 5.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which packages are affected by CVE-2020-7647?
io.jooby:jooby(maven) (versions < 2.8.2)org.jooby:jooby(maven) (versions < 2.8.2)
- Is there a fix for CVE-2020-7647? Yes. CVE-2020-7647 is fixed in 2.8.2. Upgrade to this version or later.
- Is CVE-2020-7647 exploitable, and should I be worried? Whether CVE-2020-7647 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2020-7647 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2020-7647?
- Upgrade
io.jooby:joobyto 2.8.2 or later - Upgrade
org.jooby:joobyto 2.8.2 or later
- Upgrade