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Overview

Affected versions of this package are vulnerable to Deserialization of Untrusted Data via the writeReplace() method in internal classes, which may allow a denial of service attack if combined with another exploit.

Details

Serialization is a process of converting an object into a sequence of bytes which can be persisted to a disk or database or can be sent through streams. The reverse process of creating object from sequence of bytes is called deserialization. Serialization is commonly used for communication (sharing objects between multiple hosts) and persistence (store the object state in a file or a database). It is an integral part of popular protocols like Remote Method Invocation (RMI), Java Management Extension (JMX), Java Messaging System (JMS), Action Message Format (AMF), Java Server Faces (JSF) ViewState, etc.

Deserialization of untrusted data (CWE-502), is when the application deserializes untrusted data without sufficiently verifying that the resulting data will be valid, letting the attacker to control the state or the flow of the execution.

Java deserialization issues have been known for years. However, interest in the issue intensified greatly in 2015, when classes that could be abused to achieve remote code execution were found in a popular library (Apache Commons Collection). These classes were used in zero-days affecting IBM WebSphere, Oracle WebLogic and many other products.

An attacker just needs to identify a piece of software that has both a vulnerable class on its path, and performs deserialization on untrusted data. Then all they need to do is send the payload into the deserializer, getting the command executed.

Developers put too much trust in Java Object Serialization. Some even de-serialize objects pre-authentication. When deserializing an Object in Java you typically cast it to an expected type, and therefore Java's strict type system will ensure you only get valid object trees. Unfortunately, by the time the type checking happens, platform code has already created and executed significant logic. So, before the final type is checked a lot of code is executed from the readObject() methods of various objects, all of which is out of the developer's control. By combining the readObject() methods of various classes which are available on the classpath of the vulnerable application, an attacker can execute functions (including calling Runtime.exec() to execute local OS commands).

Remediation

Upgrade com.google.code.gson:gson to version 2.8.9 or higher.

References

• GitHub Commit Introducing Vulnerable Method
• GitHub Fix Commit
• GitHub PR

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to Denial of Service (DoS). When the post request body data received by the server is greater than 16k, netty will use DiskAttribute, which will create a temporary file, and use deleteOnExit() when the file needs to be deleted, which results in DeleteOnExitHook.files continually growing and leading to a denial of service.

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

• High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

• Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.53.Final or higher.

References

• GitHub PR

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to HTTP Request Smuggling. Netty currently just skips control characters when these are present at the beginning or end of the header name. It should instead fail fast as these are not allowed by the spec and could lead to HTTP request smuggling. Failing to do the validation might cause netty to "sanitize" header names before it forward these to another remote system when used as proxy. This remote system can't see the invalid usage anymore, and therefore does not do the validation itself.

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.71.Final or higher.

References

• GitHub Commit

Overview

io.netty:netty-handler is a library that provides an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

Affected versions of this package are vulnerable to Denial of Service (DoS) such that if the user has no idle timeout handler configured it might be possible for a remote peer to send a client hello packet which leads the server to buffer up to 16MB of data per connection.

The SniHandler class is a handler that waits for the TLS handshake to configure a SslHandler according to the indicated server name by the ClientHello record. For this matter it allocates a ByteBuf using the value defined in the ClientHello record.

Note:

An attacker can craft a packet that makes the SslClientHelloHandler to:

1. Allocate a 16MB ByteBuf.

2. Not fail decode method in buffer.

3. Get out of the loop without an exception.

The combination of this without the use of a timeout makes it easy to connect to a TCP server and allocate 16MB of heap memory per connection.

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

• High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

• Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package

Remediation

Upgrade io.netty:netty-handler to version 4.1.94.Final or higher.

References

• GitHub Commit

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to Information Disclosure via the AbstractDiskHttpData method, and on Unix-like systems.

When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk are enabled. On unix-like systems, the temporary directory is shared between all users. As such, writing to this directory using API's that do not explicitly set the file/directory permissions can lead to information disclosure. The method File.createTempFile on unix-like systems creates a random file, but, by default will create this file with the permissions -rw-r--r--. Sensitive information is written to this file in AbstractDiskHttpData, and other local users can read it.

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.59.Final or higher.

References

• GitHub Commit

Overview

Affected versions of this package are vulnerable to Information Disclosure via the AbstractDiskHttpData method, and on Unix-like systems.

When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk are enabled. On unix-like systems, the temporary directory is shared between all users. As such, writing to this directory using API's that do not explicitly set the file/directory permissions can lead to information disclosure. The method File.createTempFile on unix-like systems creates a random file, but, by default will create this file with the permissions -rw-r--r--. Sensitive information is written to this file in AbstractDiskHttpData, and other local users can read it.

Remediation

Upgrade io.netty:netty-common to version 4.1.59.Final or higher.

References

• GitHub Commit

Overview

io.netty:netty-handler is a library that provides an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which enables quick and easy development of network applications such as protocol servers and clients. It greatly simplifies and streamlines network programming such as TCP and UDP socket server.

Affected versions of this package are vulnerable to Information Disclosure via the AbstractDiskHttpData method, and on Unix-like systems.

When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk are enabled. On unix-like systems, the temporary directory is shared between all users. As such, writing to this directory using API's that do not explicitly set the file/directory permissions can lead to information disclosure. The method File.createTempFile on unix-like systems creates a random file, but, by default will create this file with the permissions -rw-r--r--. Sensitive information is written to this file in AbstractDiskHttpData, and other local users can read it.

Remediation

Upgrade io.netty:netty-handler to version 4.1.59.Final or higher.

References

• GitHub Commit

Overview

Affected versions of this package are vulnerable to Information Disclosure via the AbstractDiskHttpData method, and on Unix-like systems.

When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory if temporary storing uploads on the disk are enabled. On unix-like systems, the temporary directory is shared between all users. As such, writing to this directory using API's that do not explicitly set the file/directory permissions can lead to information disclosure. The method File.createTempFile on unix-like systems creates a random file, but, by default will create this file with the permissions -rw-r--r--. Sensitive information is written to this file in AbstractDiskHttpData, and other local users can read it.

Remediation

Upgrade io.netty:netty-transport to version 4.1.59.Final or higher.

References

• GitHub Commit

Overview

Affected versions of this package are vulnerable to Integer Overflow or Wraparound in the org.threeten.bp.format.DateTimeFormatter::parse(CharSequence, ParsePosition) method, when the string is empty, the parameter index is 10, and the errorIndex is 10.

Remediation

There is no fixed version for org.threeten:threetenbp.

References

• GitHub Gist
• Vulnerable Code

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to HTTP Request Smuggling. If a Content-Length header is present in the original HTTP/2 request, the field is not validated by Http2MultiplexHandler as it is propagated up.

An additional case of this vulnerability was fixed in 4.1.61.Final (CVE-2021-21409).

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.60.Final or higher.

References

• GitHub Commit
• GitHub PR
• HTTP/2: The Sequel is Always Worse
• HTTP Request Smuggling Burp App
• HTTP Request Smuggling Demystified - Snyk Blog

Overview

Affected versions of this package are vulnerable to Information Exposure due to an incomplete fix to CVE-2021-21290, which still allowed one exploitable path. When netty's multipart decoders are used, local information disclosure can occur via the local system temporary directory, if temporary storing uploads on the disk is enabled. Note: To be vulnerable, a victim application has to run on a Unix-like operating system, and with Java 6 or below.

Remediation

Upgrade io.netty:netty-common to version 4.1.77.Final or higher.

References

• GitHub Commit

Overview

io.netty:netty-codec-http is a network application framework for rapid development of maintainable high performance protocol servers & clients.

Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling due to the accumulation of data in the HttpPostRequestDecoder. The decoder cumulates bytes in the undecodedChunk buffer until it can decode a field, allowing for data to accumulate without limits.

An attacker can cause a denial of service by sending a chunked post consisting of many small fields that will be accumulated in the bodyListHttpData list.

Remediation

Upgrade io.netty:netty-codec-http to version 4.1.108.Final or higher.

References

• GitHub Commit
• GitHub Gist

Overview

org.apache.httpcomponents:httpclient is a HttpClient component of the Apache HttpComponents project.

Affected versions of this package are vulnerable to Improper Input Validation. Apache HttpClient can misinterpret malformed authority component in request URIs passed to the library as java.net.URI object and pick the wrong target host for request execution.

Remediation

Upgrade org.apache.httpcomponents:httpclient to version 4.5.13 or higher.

References

• Apache Security Advisory
• GitHub Commit
• GitHub Commit

Overview

Affected versions of this package are vulnerable to NULL Pointer Dereference via the org.threeten.bp.LocalDate::compareTo(ChronoLocalDate) method. An attacker can trigger a NullPointerException by supplying a null object as an argument to the other parameter.

Remediation

There is no fixed version for org.threeten:threetenbp.

References

• GitHub Gist
• Vulnerable Code