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:
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
${jetty.home}/modules/ssl.modto${jetty.base}/modules - Edit the
${jetty.base}/modules/ssl.modfile to have the following section:
[lib]
lib/sslfix6072.jar
- Copy the file
${jetty.home}/etc/jetty-https.xmland${jetty.home}/etc/jetty-http2.xmlto${jetty.base}/etc - Edit files
${jetty.base}/etc/jetty-https.xmland${jetty.base}/etc/jetty-http2.xml, changing any reference oforg.eclipse.jetty.server.SslConnectionFactorytoorg.eclipse.jetty.server.ssl.fix6072.SpaceCheckingSslConnectionFactory. For example:
<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
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Java / Kotlin (Maven) | org.eclipse.jetty:jetty-server | >= 7.2.2, < 9.4.39, >= 10.0.0, < 10.0.2, >= 11.0.0, < 11.0.2 | 9.4.39, 10.0.2, 11.0.2 |
References
- https://github.com/eclipse/jetty.project/security/advisories/GHSA-26vr-8j45-3r4w
- https://nvd.nist.gov/vuln/detail/CVE-2021-28165
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://lists.apache.org/thread.html/rc907ed7b089828364437de5ed57fa062330970dc1bc5cd214b711f77@%3Ccommits.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/rc6c43c3180c0efe00497c73dd374cd34b62036cb67987ad42c1f2dce@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rc4dbc9907b0bdd634200ac90a15283d9c143c11af66e7ec72128d020@%3Cjira.kafka.apache.org%3E
- https://lists.apache.org/thread.html/rc4779abc1cface47e956cf9f8910f15d79c24477e7b1ac9be076a825@%3Cjira.kafka.apache.org%3E
- https://lists.apache.org/thread.html/rbd9a837a18ca57ac0d9b4165a6eec95ee132f55d025666fe41099f33@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rbcd7b477df55857bb6cae21fcc4404683ac98aac1a47551f0dc55486@%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/rbc075a4ac85e7a8e47420b7383f16ffa0af3b792b8423584735f369f@%3Cissues.solr.apache.org%3E
- https://lists.apache.org/thread.html/rbba0b02a3287e34af328070dd58f7828612f96e2e64992137f4dc63d@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/rbab9e67ec97591d063905bc7d4743e6a673f1bc457975fc0445ac97f@%3Cissues.hbase.apache.org%3E
- https://lists.apache.org/thread.html/rb8f5a6ded384eb00608e6137e87110e7dd7d5054cc34561cb89b81af@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rb66ed0b4bb74836add60dd5ddf9172016380b2aeefb7f96fe348537b@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rb2d34abb67cdf525945fe4b821c5cdbca29a78d586ae1f9f505a311c@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rb1624b9777a3070135e94331a428c6653a6a1edccd56fa9fb7a547f2@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rb11a13e623218c70b9f2a2d0d122fdaaf905e04a2edcd23761894464@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/rb00345f6b1620b553d2cc1acaf3017aa75cea3776b911e024fa3b187@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/raea6e820644e8c5a577f77d4e2044f8ab52183c2536b00c56738beef@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rae8bbc5a516f3e21b8a55e61ff6ad0ced03bdbd116d2170a3eed9f5c@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/ra9dd15ba8a4fb7e42c7fe948a6d6b3868fd6bbf8e3fb37fcf33b2cd0@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/ra50519652b0b7f869a14fbfb4be9758a29171d7fe561bb7e036e8449@%3Cissues.hbase.apache.org%3E
- https://lists.apache.org/thread.html/ra21b3e6bd9669377139fe33fb46edf6fece3f31375bc42a0dcc964b2@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/ra210e38ae0bf615084390b26ba01bb5d66c0a76f232277446ae0948a@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r9fae5a4087d9ed1c9d4f0c7493b6981a4741cfb4bebb2416da638424@%3Cissues.spark.apache.org%3E
- https://lists.apache.org/thread.html/r9db72e9c33b93eba45a214af588f1d553839b5c3080fc913854a49ab@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r9b793db9f395b546e66fb9c44fe1cd75c7755029e944dfee31b8b779@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/r9974f64723875052e02787b2a5eda689ac5247c71b827d455e5dc9a6@%3Cissues.solr.apache.org%3E
- https://lists.apache.org/thread.html/r4abbd760d24bab2b8f1294c5c9216ae915100099c4391ad64e9ae38b@%3Cdev.hbase.apache.org%3E
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.debian.org/security/2021/dsa-4949
- https://security.netapp.com/advisory/ntap-20210611-0006
- https://lists.apache.org/thread.html/rfd3ff6e66b6bbcfb2fefa9f5a20328937c0369b2e142e3e1c6774743@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rfc9f51b4e21022b3cd6cb6f90791a6a6999560212e519b5f09db0aed@%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/rf99f9a25ca24fe519c9346388f61b5b3a09be31b800bf37f01473ad7@%3Cnotifications.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf6de4c249bd74007f5f66f683c110535f46e719d2f83a41e8faf295f@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/rf1b02dfccd27b8bbc3afd119b212452fa32e9ed7d506be9357a3a7ec@%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/ree1895a256a9db951e0d97a76222909c2e1f28c1a3d89933173deed6@%3Creviews.spark.apache.org%3E
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-400, CWE-551, CWE-755- Platform
- Java / Kotlin (Maven)
- Package
org.eclipse.jetty:jetty-server- Disclosed
- 06.04.2021
- Updated
- 11.10.2026 12:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-26vr-8j45-3r4w - CC BY 4.0
Vulnerability history: org.eclipse.jetty:jetty-server
All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 29
- First → latest
- 10.2018 07.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 4
- High 10
- Medium 13
- Low 2
Disclosures per year
- 2018: 8
- 2019: 5
- 2020: 2
- 2021: 3
- 2022: 3
- 2023: 2
- 2024: 1
- 2025: 1
- 2026: 4
-
Jetty vulnerable to incorrect handling of invalid large TLS frame, exhausting CPU resources this entry
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