CVE-2022-40151

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.

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
• Contact us at XStream Google Group

XStream is a simple library to serialize objects to XML and back again. A high level facade is supplied that simplifies common use cases. Custom objects can be serialized without need for specifying mappings. Speed and low memory footprint are a crucial part of the design, making it suitable for large object graphs or systems with high message throughput. No information is duplicated that can be obtained via reflection. This results in XML that is easier to read for humans and more compact than native Java serialization. XStream serializes internal fields, including private and final. Supports non-public and inner classes. Classes are not required to have default constructor. Duplicate references encountered in the object-model will be maintained. Supports circular references. By implementing an interface, XStream can serialize directly to/from any tree structure (not just XML). Strategies can be registered allowing customization of how particular types are represented as XML. When an exception occurs due to malformed XML, detailed diagnostics are provided to help isolate and fix the problem.

Security Fix(es):

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.(CVE-2022-40151)

XStream serializes Java objects to XML and back again. Versions prior to 1.4.20 may allow a remote attacker to terminate the application with a stack overflow error, resulting in a denial of service only via manipulation the processed input stream. The attack uses the hash code implementation for collections and maps to force recursive hash calculation causing a stack overflow. This issue is patched in version 1.4.20 which handles the stack overflow and raises an InputManipulationException instead. A potential workaround for users who only use HashMap or HashSet and whose XML refers these only as default map or set, is to change the default implementation of java.util.Map and java.util per the code example in the referenced advisory. However, this implies that your application does not care about the implementation of the map and all elements are comparable.(CVE-2022-41966)

XStream is a simple library to serialize objects to XML and back again. A high level facade is supplied that simplifies common use cases. Custom objects can be serialized without need for specifying mappings. Speed and low memory footprint are a crucial part of the design, making it suitable for large object graphs or systems with high message throughput. No information is duplicated that can be obtained via reflection. This results in XML that is easier to read for humans and more compact than native Java serialization. XStream serializes internal fields, including private and final. Supports non-public and inner classes. Classes are not required to have default constructor. Duplicate references encountered in the object-model will be maintained. Supports circular references. By implementing an interface, XStream can serialize directly to/from any tree structure (not just XML). Strategies can be registered allowing customization of how particular types are represented as XML. When an exception occurs due to malformed XML, detailed diagnostics are provided to help isolate and fix the problem.

Security Fix(es):

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.(CVE-2022-40151)

XStream serializes Java objects to XML and back again. Versions prior to 1.4.20 may allow a remote attacker to terminate the application with a stack overflow error, resulting in a denial of service only via manipulation the processed input stream. The attack uses the hash code implementation for collections and maps to force recursive hash calculation causing a stack overflow. This issue is patched in version 1.4.20 which handles the stack overflow and raises an InputManipulationException instead. A potential workaround for users who only use HashMap or HashSet and whose XML refers these only as default map or set, is to change the default implementation of java.util.Map and java.util per the code example in the referenced advisory. However, this implies that your application does not care about the implementation of the map and all elements are comparable.(CVE-2022-41966)

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.

These are all security issues fixed in the xstream-1.4.20-1.1 package on the GA media of openSUSE Tumbleweed.

Root has patched CVE-2022-40151 in the io.root.com.thoughtworks.xstream:xstream package for Root:Maven. Multiple fixed versions available.

This update for xstream fixes the following issues:

• CVE-2022-40151: Fixed stackoverflow in XML serialization (bsc#1203520).

• CVE-2022-41966: Fixed denial of service via uncontrolled recursion during deserialization (bsc#1206729).

• Upgrade to 1.4.20.