High Http2 CVEs with no public exploit

CVE	Severity	Published▾	Status	Exploitation	Description
CVE-2026-48043	High	2026-06-12	No exploit published	No public exploit	Netty is a network application framework for development of protocol servers and clients. In netty-codec-http2 prior to versions 4.1.135.Final and 4.2.15.Final, the `DelegatingDecompressorFrameListener` class orchestrates HTTP/2 decompression by embedding a per-stream `EmbeddedChannel` that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled `ByteBuf` handed to an anonymous `ChannelInboundHandlerAdapter` tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
CVE-2026-33871	High	2026-03-27	No exploit published	No public exploit	Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.
CVE-2025-5115	High	2025-08-20	No exploit published	No public exploit	In Eclipse Jetty, versions <=9.4.57, <=10.0.25, <=11.0.25, <=12.0.21, <=12.1.0.alpha2, an HTTP/2 client may trigger the server to send RST_STREAM frames, for example by sending frames that are malformed or that should not be sent in a particular stream state, therefore forcing the server to consume resources such as CPU and memory. For example, a client can open a stream and then send WINDOW_UPDATE frames with window size increment of 0, which is illegal. Per specification https://www.rfc-editor.org/rfc/rfc9113.html#name-window_update , the server should send a RST_STREAM frame. The client can now open another stream and send another bad WINDOW_UPDATE, therefore causing the server to consume more resources than necessary, as this case does not exceed the max number of concurrent streams, yet the client is able to create an enormous amount of streams in a short period of time. The attack can be performed with other conditions (for example, a DATA frame for a closed stream) that cause the server to send a RST_STREAM frame. Links: * https://github.com/jetty/jetty.project/security/advisories/GHSA-mmxm-8w33-wc4h
CVE-2025-1948	High	2025-05-08	No exploit published	No public exploit	In Eclipse Jetty versions 12.0.0 to 12.0.16 included, an HTTP/2 client can specify a very large value for the HTTP/2 settings parameter SETTINGS_MAX_HEADER_LIST_SIZE. The Jetty HTTP/2 server does not perform validation on this setting, and tries to allocate a ByteBuffer of the specified capacity to encode HTTP responses, likely resulting in OutOfMemoryError being thrown, or even the JVM process exiting.
CVE-2023-36478	High	2023-10-10	No exploit published	No public exploit	Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded. However, when length is very large and huffman is true, the multiplication by 4 in line 295 will overflow, and length will become negative. `(_size+length)` will now be negative, and the check on line 296 will not be triggered. Furthermore, `MetaDataBuilder.checkSize` allows for user-entered HPACK header value sizes to be negative, potentially leading to a very large buffer allocation later on when the user-entered size is multiplied by 2. This means that if a user provides a negative length value (or, more precisely, a length value which, when multiplied by the 4/3 fudge factor, is negative), and this length value is a very large positive number when multiplied by 2, then the user can cause a very large buffer to be allocated on the server. Users of HTTP/2 can be impacted by a remote denial of service attack. The issue has been fixed in versions 11.0.16, 10.0.16, and 9.4.53. There are no known workarounds.
CVE-2022-2048	High	2022-07-07	No exploit published	No public exploit	In Eclipse Jetty HTTP/2 server implementation, when encountering an invalid HTTP/2 request, the error handling has a bug that can wind up not properly cleaning up the active connections and associated resources. This can lead to a Denial of Service scenario where there are no enough resources left to process good requests.

CVE

Severity

Published▾

Status

Exploitation

Description

CVE-2026-48043

High

2026-06-12

No exploit published

No public exploit

Netty is a network application framework for development of protocol servers and clients. In netty-codec-http2 prior to versions 4.1.135.Final and 4.2.15.Final, the `DelegatingDecompressorFrameListener` class orchestrates HTTP/2 decompression by embedding a per-stream `EmbeddedChannel` that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled `ByteBuf` handed to an anonymous `ChannelInboundHandlerAdapter` tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

CVE-2026-33871

High

2026-03-27

No exploit published

No public exploit

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

CVE-2025-5115

High

2025-08-20

No exploit published

No public exploit

In Eclipse Jetty, versions <=9.4.57, <=10.0.25, <=11.0.25, <=12.0.21, <=12.1.0.alpha2, an HTTP/2 client may trigger the server to send RST_STREAM frames, for example by sending frames that are malformed or that should not be sent in a particular stream state, therefore forcing the server to consume resources such as CPU and memory. For example, a client can open a stream and then send WINDOW_UPDATE frames with window size increment of 0, which is illegal. Per specification https://www.rfc-editor.org/rfc/rfc9113.html#name-window_update , the server should send a RST_STREAM frame. The client can now open another stream and send another bad WINDOW_UPDATE, therefore causing the server to consume more resources than necessary, as this case does not exceed the max number of concurrent streams, yet the client is able to create an enormous amount of streams in a short period of time. The attack can be performed with other conditions (for example, a DATA frame for a closed stream) that cause the server to send a RST_STREAM frame. Links: * https://github.com/jetty/jetty.project/security/advisories/GHSA-mmxm-8w33-wc4h

CVE-2025-1948

High

2025-05-08

No exploit published

No public exploit

In Eclipse Jetty versions 12.0.0 to 12.0.16 included, an HTTP/2 client can specify a very large value for the HTTP/2 settings parameter SETTINGS_MAX_HEADER_LIST_SIZE. The Jetty HTTP/2 server does not perform validation on this setting, and tries to allocate a ByteBuffer of the specified capacity to encode HTTP responses, likely resulting in OutOfMemoryError being thrown, or even the JVM process exiting.

CVE-2023-36478

High

2023-10-10

No exploit published

No public exploit

Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded. However, when length is very large and huffman is true, the multiplication by 4 in line 295 will overflow, and length will become negative. `(_size+length)` will now be negative, and the check on line 296 will not be triggered. Furthermore, `MetaDataBuilder.checkSize` allows for user-entered HPACK header value sizes to be negative, potentially leading to a very large buffer allocation later on when the user-entered size is multiplied by 2. This means that if a user provides a negative length value (or, more precisely, a length value which, when multiplied by the 4/3 fudge factor, is negative), and this length value is a very large positive number when multiplied by 2, then the user can cause a very large buffer to be allocated on the server. Users of HTTP/2 can be impacted by a remote denial of service attack. The issue has been fixed in versions 11.0.16, 10.0.16, and 9.4.53. There are no known workarounds.

CVE-2022-2048

High

2022-07-07

No exploit published

No public exploit

In Eclipse Jetty HTTP/2 server implementation, when encountering an invalid HTTP/2 request, the error handling has a bug that can wind up not properly cleaning up the active connections and associated resources. This can lead to a Denial of Service scenario where there are no enough resources left to process good requests.