CVE-2026-107227CWE-400CWE-409denial-of-service

CVE-2026-107227

High · published October 8, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
36.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00432 · 36.4th percentile
Weaknesses
CWE-400 · Uncontrolled Resource Consumption; CWE-409 · Improper Handling of Highly Compressed Data (Data Amplification)
Published
2026-10-08T01:17Z
References (3)
https://github.com/AsyncHttpClient/async-http-client/commit/b61637f30327f314b7693418f12ce141ac6b2b30 · [email protected]https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-3.0.14 · [email protected]https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-x8v2-478q-2hvg · [email protected]
EPSS history
Timeline
  • 09 OCT 03:26Z
    EPSS moved — → 0%
    epss
  • 07 OCT 20:51Z
    AsyncHttpClient: Unbounded WebSocket permessage-deflate decompression enables a decompression-bomb denial of service when compression is enabled
    cvelistv5
  • 07 OCT 20:51Z
    AsyncHttpClient: Unbounded WebSocket permessage-deflate decompression enables a decompression-bomb denial of service when compression is enabled
    cvelistv5