AsyncHttpClient up to 2.16.0/3.0.12 Realm.Builder improper authentication

Summaryinfo

A vulnerability labeled as problematic has been found in AsyncHttpClient up to 2.16.0/3.0.12. The impacted element is an unknown function of the component Realm.Builder. Executing a manipulation can lead to improper authentication. This vulnerability is registered as CVE-2026-107231. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in AsyncHttpClient up to 2.16.0/3.0.12. This vulnerability affects an unknown part of the component Realm.Builder. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality. CVE summarizes:

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. Prior to 3.0.13 and 2.16.1, Realm.Builder treats a Digest challenge that yields no usable nonce as a Basic challenge. A malicious origin or proxy can label a challenge Digest while omitting or emptying the nonce, causing the client to resend the username and password using reversible Basic authentication. Both origin and proxy challenge parsers are affected. This issue is fixed in versions 3.0.13 and 2.16.1.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-107231 since 10/07/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 2.16.1 or 3.0.13 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• AsyncHttpClient

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
• 3.0.12

CPE 2.3info

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CPE 2.2info

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