async-http-client up to 2.16.0/3.0.11 Handshake WebSocketHandler.upgrade Sec-WebSocket-Accept input validation

Summaryinfo

A vulnerability has been found in async-http-client up to 2.16.0/3.0.11 and classified as problematic. This vulnerability affects the function WebSocketHandler.upgrade of the component Handshake. The manipulation of the argument Sec-WebSocket-Accept leads to input validation. This vulnerability is uniquely identified as CVE-2026-107284. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in async-http-client up to 2.16.0/3.0.11. It has been rated as problematic. This issue affects the function WebSocketHandler.upgrade of the component Handshake. The manipulation of the argument Sec-WebSocket-Accept with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is integrity. The summary by CVE is:

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. Prior to 3.0.12 and 2.16.1, WebSocketHandler.upgrade aborts a handshake whose Sec-WebSocket-Accept value is missing or invalid but continues into pipeline installation and onOpen delivery. Frames coalesced with the invalid 101 response can be decoded and delivered from a peer that did not prove the handshake, although the request future fails and the channel closes. This issue is fixed in versions 3.0.12 and 2.16.1.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-107284 since 10/07/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 2.16.1 or 3.0.12 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

• async-http-client

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16.0
• 3.0.0
• 3.0.1
• 3.0.2
• 3.0.3
• 3.0.4
• 3.0.5
• 3.0.6
• 3.0.7
• 3.0.8
• 3.0.9
• 3.0.10
• 3.0.11

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

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• 🔒
• 🔒

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