# 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.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Oct 2026
- **Updated:** 8 Oct 2026
- **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

## 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.

Weakness: CWE-409 (Improper Handling of Highly Compressed Data (Data Amplification)), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-107227?

4 open source packages ship an affected version, including org.asynchttpclient:async-http-client.


| Package | Ecosystem | 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.

## Is CVE-2026-107227 being exploited?

There is no known exploitation of CVE-2026-107227 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107227 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-107227 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.asynchttpclient:async-http-client (Maven): affected from 2.2.0 up to 2.16.1; no fix listed
- org.asynchttpclient:async-http-client (Maven): affected from 2.2.0 up to 2.16.1; no fix listed
- org.asynchttpclient:async-http-client (Maven): affected from 3.0.0; fixed in 3.0.14
- org.asynchttpclient:async-http-client (Maven): affected from 3.0.0; fixed in 3.0.14

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-107227/ (Markdown: https://insights.sbomify.com/CVE-2026-107227/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107227
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107227
- OSV: https://osv.dev/vulnerability/CVE-2026-107227

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107227/
Summaries are generated and may contain mistakes; the official description above is the record.