AsyncHttpClient leaks authorization credentials to untrusted domains on cross-origin redirects
Summary
| CVE | CVE-2026-40490 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-18 02:16:11 UTC |
| Updated | 2026-04-18 02:16:11 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 6.8 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Problem Types: CWE-200 | CWE-200 CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 6.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N |
| 3.1 | CNA | DECLARED | 6.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
ChangedConfidentiality
HighIntegrity
NoneAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | AsyncHttpClient | Async-http-client | affected >= 3.0.0.Beta1, < 3.0.9 | Not specified |
| CNA | AsyncHttpClient | Async-http-client | affected < 2.14.5 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-cm... | [email protected] | github.com | |
| github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-cli... | [email protected] | github.com | |
| github.com/AsyncHttpClient/async-http-client/commit/6b2fbb7f8 | [email protected] | github.com | |
| github.com/AsyncHttpClient/async-http-client/commit/ae557ad35246721c09da... | [email protected] | github.com | |
| github.com/AsyncHttpClient/async-http-client/releases/tag/async-http-cli... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.