Package Instance

XStream can cause Denial of Service via stack overflow
### Impact
The vulnerability may allow a remote attacker to terminate the application with a stack overflow error resulting in a denial of service only by manipulating the processed input stream.

### Patches
XStream 1.4.20 handles the stack overflow and raises an InputManipulationException instead.

### Workarounds
The attack uses the hash code implementation for collections and maps to force recursive hash calculation causing a stack overflow. Following types of the Java runtime are affected:

- java.util.HashMap
- java.util.HashSet
- java.util.Hashtable
- java.util.LinkedHashMap
- java.util.LinkedHashSet
- Other third party collection implementations that use their element's hash code may also be affected

A simple solution is to catch the StackOverflowError in the client code calling XStream.

If your object graph does not use referenced elements at all, you may simply set the NO_REFERENCE mode:
```Java
XStream xstream = new XStream();
xstream.setMode(XStream.NO_REFERENCES);
```

If your object graph contains neither a Hashtable, HashMap nor a HashSet (or one of the linked variants of it) then you can use the security framework to deny the usage of these types:
```Java
XStream xstream = new XStream();
xstream.denyTypes(new Class[]{
 java.util.HashMap.class, java.util.HashSet.class, java.util.Hashtable.class, java.util.LinkedHashMap.class, java.util.LinkedHashSet.class
});
```

Unfortunately these types are very common. If you only use HashMap or HashSet and your XML refers these only as default map or set, you may additionally change the default implementation of java.util.Map and java.util.Set at unmarshalling time::
```Java
xstream.addDefaultImplementation(java.util.TreeMap.class, java.util.Map.class);
xstream.addDefaultImplementation(java.util.TreeSet.class, java.util.Set.class);
```
However, this implies that your application does not care about the implementation of the map and all elements are comparable.

### References
See full information about the nature of the vulnerability and the steps to reproduce it in XStream's documentation for [CVE-2022-41966](https://x-stream.github.io/CVE-2022-41966.html).

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [XStream](https://github.com/x-stream/xstream/issues)
* Contact us at [XStream Google Group](https://groups.google.com/group/xstream-user)

Duplicate Advisory: Denial of Service due to parser crash
## Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of [GHSA-f8cc-g7j8-xxpm](https://github.com/advisories/GHSA-f8cc-g7j8-xxpm). This link is maintained to preserve external references.

## Original Description
Those using Xstream to seralize XML data may be vulnerable to Denial of Service attacks (DOS). If the parser is running on user supplied input, an attacker may supply content that causes the parser to crash by stackoverflow. This effect may support a denial of service attack.

XStream is vulnerable to a Denial of Service attack due to stack overflow from a manipulated binary input stream
### Impact
The vulnerability may allow a remote attacker to terminate the application with a stack overflow error resulting in a denial of service only by manipulating the processed input stream when XStream is configured to use the BinaryStreamDriver.

### Patches
XStream 1.4.21 detects the manipulation in the binary input stream causing the the stack overflow and raises an InputManipulationException instead.

### Workarounds
The only solution is to catch the StackOverflowError in the client code calling XStream if XStream is configured to use the BinaryStreamDriver.

### References
See full information about the nature of the vulnerability and the steps to reproduce it in XStream's documentation for [CVE-2024-47072](https://x-stream.github.io/CVE-2024-47072.html).

### Credits
Alexis Challande of Trail Of Bits found and reported the issue to XStream and provided the required information to reproduce it.

Denial of Service due to parser crash
Those using FasterXML/woodstox to seralize XML data may be vulnerable to Denial of Service attacks (DOS). If the parser is running on user supplied input, an attacker may supply content that causes the parser to crash by stackoverflow. This effect may support a denial of service attack.

This vulnerability is only relevant for users making use of the DTD parsing functionality.

XStream can cause a Denial of Service by injecting deeply nested objects raising a stack overflow
### Impact
The vulnerability may allow a remote attacker to terminate the application with a stack overflow error resulting in a denial of service only by manipulating the processed input stream.

### Patches
XStream 1.4.20 handles the stack overflow and raises an InputManipulationException instead.

### Workarounds
The only solution is to catch the StackOverflowError in the client code calling XStream.

### References
See full information about the nature of the vulnerability and the steps to reproduce it in XStream's documentation for [CVE-2022-40151](https://x-stream.github.io/CVE-2022-40151.html).

### Credits
The vulnerability was discovered and reported by Henry Lin of the Google OSS-Fuzz team.

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [XStream](https://github.com/x-stream/xstream/issues)
* Contact us at [XStream Google Group](https://groups.google.com/group/xstream-user)

Denial of Service by injecting highly recursive collections or maps in XStream
The vulnerability may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service only by manipulating the processed input stream.

Server-Side Request Forgery (SSRF)
XStream is a simple library to serialize objects to XML and back again. This vulnerability may allow a remote attacker to request data from internal resources that are not publicly available only by manipulating the processed input stream with a Java runtime to Users who followed the recommendation to setup XStream's security framework with an allow list limited to the minimal required types are not impacted.

Deserialization of Untrusted Data
XStream is a simple library to serialize objects to XML and back again. This vulnerability may allow a remote attacker to load and execute arbitrary code from a remote host only by manipulating the processed input stream. Users who followed the recommendation to setup XStream's security framework with an allow list limited to the minimal required types are not impacted.