CVE-2026-107285 AsyncHttpClient CVE debrief

Who should care

Defenders responsible for Java applications using the AsyncHttpClient library, particularly those using proxied WebSocket requests, should assess potential exposure and implement compensating controls.

Why it matters

The vulnerability in AsyncHttpClient could lead to exposure of proxy credentials and potential security risks for Java applications using proxied WebSocket requests.

• Potential exposure of proxy credentials
• Possible replay or offline cracking of Digest responses
• Need for verification of AsyncHttpClient version and configurations
• Potential impact on confidentiality

Technical summary

The AsyncHttpClient library, used for HTTP requests in Java applications, had a vulnerability prior to versions 3.0.12 and 2.16.1. When using a proxied WebSocket (ws) request, the CONNECT tunnel would send the proxy's authentication credentials to the origin server. This happened because the library only checked if the URI was secure to decide whether to attach proxy authentication, and since ws is not considered secure, the credentials were included.

Defensive priority

Defenders should prioritize verifying their inventory of AsyncHttpClient versions and upgrading to 3.0.12 or 2.16.1 if necessary. They should also review their configurations for proxied WebSocket requests and assess potential exposure.

Recommended defensive actions

• Verify AsyncHttpClient version and upgrade if necessary
• Review configurations for proxied WebSocket requests
• Assess potential exposure and implement compensating controls
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and source item provide details on the vulnerability, its impact, and the fixed versions. However, there is limited information on potential exploitation or affected systems. Defenders should verify the AsyncHttpClient version, review configurations for proxied WebSocket requests, and assess potential exposure. Evidence from the CVE record and source item should be used to ground the response, with explicit language on evidence limits and defensive verification tasks. Limited source detail exists on affected scope and 3

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.