CVE-2026-85717: AsyncHttpClient: Client-wide realm credentials re-sent to a cross-origin redirect target

Severity: medium (CVSS 6.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-17 · updated 2026-09-30
Weakness: CWE-200

Description

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. From 2.14.5 to 2.16.0 and from 3.0.9 to 3.0.11, a client configured with a client-wide Realm and redirect following can disclose credentials after a cross-origin redirect because the Interceptors authentication path falls back to the client configuration after redirect handling clears the per-exchange realm. If the attacker-controlled target returns 401, the client can send Basic or Digest credentials or a Negotiate or NTLM token to that origin. Per-request realms are stripped correctly, and this issue is a residual bypass of the earlier cross-origin credential-stripping fixes. This issue is fixed in versions 2.16.1 and 3.0.12.

Affected products

AsyncHttpClient async-http-client: from 2.14.5, < 2.16.1; from 3.0.9, < 3.0.12

References

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