CVE-2026-107227
Description
A flaw was found in AsyncHttpClient's WebSocket permessage-deflate handling. When WebSocket compression is enabled (it is disabled by default), the client does not limit the size of a message after decompression; the configured frame and buffer limits apply to the compressed data. A malicious or compromised WebSocket server, or an attacker able to interfere with a cleartext ws:// connection, can send a small compressed message that expands substantially and exhausts the client's JVM heap, causing denial of service. The issue is fixed in AsyncHttpClient 3.0.14. The 2.x line is end of life and has no fix.
Statement
This vulnerability is rated as an Important impact because an unauthenticated remote peer can cause process termination or severe denial of service by exhausting the JVM memory pool. However, exploitation requires the client to explicitly enable WebSocket compression, an option that remains disabled by default. Furthermore, the risk is largely confined to environments that connect to untrusted endpoints or transmit over unencrypted transport channels where message interception is possible.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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