CVE-2021-29425 PoC — Apache Commons IO 路径遍历漏洞

介绍

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 | 1) Re-generate using: mvn commons:readme-md                          |
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 | 2) Set the following properties in the component's pom:              |
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 | 3) Example Properties                                                |
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Apache Commons IO
===================

[![Build Status](https://travis-ci.org/apache/commons-io.svg?branch=master)](https://travis-ci.org/apache/commons-io)
[![Coverage Status](https://coveralls.io/repos/apache/commons-io/badge.svg?branch=master)](https://coveralls.io/r/apache/commons-io)
[![Maven Central](https://maven-badges.herokuapp.com/maven-central/commons-io/commons-io/badge.svg)](https://maven-badges.herokuapp.com/maven-central/commons-io/commons-io/)
[![License](http://img.shields.io/:license-apache-blue.svg)](http://www.apache.org/licenses/LICENSE-2.0.html)

The Apache Commons IO library contains utility classes, stream implementations, file filters,
file comparators, endian transformation classes, and much more.

Documentation
-------------

More information can be found on the [Apache Commons IO homepage](https://commons.apache.org/proper/commons-io).
The [JavaDoc](https://commons.apache.org/proper/commons-io/javadocs/api-release) can be browsed.
Questions related to the usage of Apache Commons IO should be posted to the [user mailing list][ml].

Where can I get the latest release?
-----------------------------------
You can download source and binaries from our [download page](https://commons.apache.org/proper/commons-io/download_io.cgi).

Alternatively you can pull it from the central Maven repositories:

```xml
<dependency>
  <groupId>commons-io</groupId>
  <artifactId>commons-io</artifactId>
  <version>2.6</version>
</dependency>
```

Contributing
------------

We accept Pull Requests via GitHub. The [developer mailing list][ml] is the main channel of communication for contributors.
There are some guidelines which will make applying PRs easier for us:
+ No tabs! Please use spaces for indentation.
+ Respect the code style.
+ Create minimal diffs - disable on save actions like reformat source code or organize imports. If you feel the source code should be reformatted create a separate PR for this change.
+ Provide JUnit tests for your changes and make sure your changes don't break any existing tests by running ```mvn clean test```.

If you plan to contribute on a regular basis, please consider filing a [contributor license agreement](https://www.apache.org/licenses/#clas).
You can learn more about contributing via GitHub in our [contribution guidelines](CONTRIBUTING.md).

License
-------
This code is under the [Apache Licence v2](https://www.apache.org/licenses/LICENSE-2.0).

See the `NOTICE.txt` file for required notices and attributions.

Donations
---------
You like Apache Commons IO? Then [donate back to the ASF](https://www.apache.org/foundation/contributing.html) to support the development.

Additional Resources
--------------------

+ [Apache Commons Homepage](https://commons.apache.org/)
+ [Apache Issue Tracker (JIRA)](https://issues.apache.org/jira/browse/IO)
+ [Apache Commons Twitter Account](https://twitter.com/ApacheCommons)
+ `#apache-commons` IRC channel on `irc.freenode.org`

[ml]:https://commons.apache.org/mail-lists.html

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