CVE-2026-107227 AsyncHttpClient: Unbounded WebSocket permessage-deflate decompression enables a decompression-bomb denial of service when compression is enabled
A malicious WebSocket peer can cause a denial of service via decompression bomb in AsyncHttpClient when compression is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107227?
CVE-2026-107227 is a high-severity denial of service vulnerability in AsyncHttpClient async-http-client, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. From 2.2.0 until 3.0.14, WebSocket permessage-deflate decompression is unbounded when compression is enabled. The inbound pipeline aggregates compressed frames before WebSocketClientCompressionHandler inflates them, so webSocketMaxFrameSize and webSocketMaxBufferSize do not bound decompressed output. A malicious WebSocket peer can send a small compressed message that expands to a very large Netty buffer and exhausts JVM heap. This issue is fixed in version 3.0.14.
Which versions are affected by CVE-2026-107227?
4 open source packages ship an affected version, including org.asynchttpclient:async-http-client.
| Package | Affected | Fixed in |
|---|---|---|
org.asynchttpclient:async-http-client Maven | From 2.2.0 to 2.16.1 | None |
org.asynchttpclient:async-http-client Maven | From 2.2.0 to 2.16.1 | None |
org.asynchttpclient:async-http-client Maven | From 3.0.0 | 3.0.14 |
org.asynchttpclient:async-http-client Maven | From 3.0.0 | 3.0.14 |
How do I fix CVE-2026-107227?
Upgrade org.asynchttpclient:async-http-client to 3.0.14 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-107227 being exploited?
There is no known exploitation of CVE-2026-107227 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-107227, GHSA-x8v2-478q-2hvg, MINI-f9x6-gqrq-p57g, MINI-mf6c-4ggv-524q, ROOT-APP-MAVEN-CVE-2026-107227, UBUNTU-CVE-2026-107227.