Package Instance

Lack of type validation in agent related REST API in Jenkins
Jenkins 2.286 and earlier, LTS 2.277.1 and earlier does not validate the type of object created after loading the data submitted to the `config.xml` REST API endpoint of a node.

This allows attackers with Computer/Configure permission to replace a node with one of a different type.

Jenkins 2.287, LTS 2.277.2 validates the type of object created and rejects objects of unexpected types.

View name validation bypass in Jenkins
Jenkins 2.286 and earlier, LTS 2.277.1 and earlier does not properly check that a newly created view has an allowed name. When a form to create a view is submitted, the name is included twice in the submission. One instance is validated, but the other instance is used to create the value.

This allows attackers with View/Create permission to create views with invalid or already-used names.

Jenkins 2.287, LTS 2.277.2 uses the same submitted value for validation and view creation.

Jetty vulnerable to incorrect handling of invalid large TLS frame, exhausting CPU resources
### Impact
When using SSL/TLS with Jetty, either with HTTP/1.1, HTTP/2, or WebSocket, the server may receive an invalid large (greater than 17408) TLS frame that is incorrectly handled, causing CPU resources to eventually reach 100% usage.

### Workarounds

The problem can be worked around by compiling the following class:
```java
package org.eclipse.jetty.server.ssl.fix6072;

import java.nio.ByteBuffer;
import javax.net.ssl.SSLEngine;
import javax.net.ssl.SSLEngineResult;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLHandshakeException;

import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.io.ssl.SslConnection;
import org.eclipse.jetty.server.Connector;
import org.eclipse.jetty.server.SslConnectionFactory;
import org.eclipse.jetty.util.BufferUtil;
import org.eclipse.jetty.util.annotation.Name;
import org.eclipse.jetty.util.ssl.SslContextFactory;

public class SpaceCheckingSslConnectionFactory extends SslConnectionFactory
{
    public SpaceCheckingSslConnectionFactory(@Name("sslContextFactory") SslContextFactory factory, @Name("next") String nextProtocol)
    {
        super(factory, nextProtocol);
    }

    @Override
    protected SslConnection newSslConnection(Connector connector, EndPoint endPoint, SSLEngine engine)
    {
        return new SslConnection(connector.getByteBufferPool(), connector.getExecutor(), endPoint, engine, isDirectBuffersForEncryption(), isDirectBuffersForDecryption())
        {
            @Override
            protected SSLEngineResult unwrap(SSLEngine sslEngine, ByteBuffer input, ByteBuffer output) throws SSLException
            {
                SSLEngineResult results = super.unwrap(sslEngine, input, output);

                if ((results.getStatus() == SSLEngineResult.Status.BUFFER_UNDERFLOW ||
                    results.getStatus() == SSLEngineResult.Status.OK && results.bytesConsumed() == 0 && results.bytesProduced() == 0) &&
                    BufferUtil.space(input) == 0)
                {
                    BufferUtil.clear(input);
                    throw new SSLHandshakeException("Encrypted buffer max length exceeded");
                }
                return results;
            }
        };
    }
}
```
This class can be deployed by:
 + The resulting class file should be put into a jar file (eg sslfix6072.jar)
 + The jar file should be made available to the server. For a normal distribution this can be done by putting the file into ${jetty.base}/lib
 + Copy the file `${jetty.home}/modules/ssl.mod` to `${jetty.base}/modules`
 + Edit the `${jetty.base}/modules/ssl.mod` file to have the following section:

```
[lib]
lib/sslfix6072.jar
```

+ Copy the file `${jetty.home}/etc/jetty-https.xml` and`${jetty.home}/etc/jetty-http2.xml` to `${jetty.base}/etc`
+ Edit files `${jetty.base}/etc/jetty-https.xml` and `${jetty.base}/etc/jetty-http2.xml`, changing any reference of `org.eclipse.jetty.server.SslConnectionFactory` to `org.eclipse.jetty.server.ssl.fix6072.SpaceCheckingSslConnectionFactory`. For example:
```xml
  <Call name="addIfAbsentConnectionFactory">
    <Arg>
      <New class="org.eclipse.jetty.server.ssl.fix6072.SpaceCheckingSslConnectionFactory">
        <Arg name="next">http/1.1</Arg>
        <Arg name="sslContextFactory"><Ref refid="sslContextFactory"/></Arg>
      </New>
    </Arg>
  </Call>
```
+ Restart Jetty