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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-40490 Detail

Description

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. When redirect following is enabled (followRedirect(true)), versions of AsyncHttpClient prior to 3.0.9 and 2.14.5 forward Authorization and Proxy-Authorization headers along with Realm credentials to arbitrary redirect targets regardless of domain, scheme, or port changes. This leaks credentials on cross-domain redirects and HTTPS-to-HTTP downgrades. Additionally, even when stripAuthorizationOnRedirect is set to true, the Realm object containing plaintext credentials is still propagated to the redirect request, causing credential re-generation for Basic and Digest authentication schemes via NettyRequestFactory. An attacker who controls a redirect target (via open redirect, DNS rebinding, or MITM on HTTP) can capture Bearer tokens, Basic auth credentials, or any other Authorization header value. The fix in versions 3.0.9 and 2.14.5 automatically strips Authorization and Proxy-Authorization headers and clears Realm credentials whenever a redirect crosses origin boundaries (different scheme, host, or port) or downgrades from HTTPS to HTTP. For users unable to upgrade, set `(stripAuthorizationOnRedirect(true))` in the client config and avoid using Realm-based authentication with redirect following enabled. Note that `(stripAuthorizationOnRedirect(true))` alone is insufficient on versions prior to 3.0.9 and 2.14.5 because the Realm bypass still re-generates credentials. Alternatively, disable redirect following (`followRedirect(false)`) and handle redirects manually with origin validation.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/AsyncHttpClient/async-http-client/commit/6b2fbb7f8 GitHub, Inc.
https://github.com/AsyncHttpClient/async-http-client/commit/ae557ad35246721c09dafb2976609cd0004e78ae GitHub, Inc.
https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-2.14.5 GitHub, Inc.
https://github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-client-project-3.0.9 GitHub, Inc.
https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-cmxv-58fp-fm3g GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-40490
NVD Published Date:
04/17/2026
NVD Last Modified:
04/17/2026
Source:
GitHub, Inc.