GHSA-CMXV-58FP-FM3G
Vulnerability from github – Published: 2026-04-14 01:07 – Updated: 2026-04-15 21:00Impact
When redirect following is enabled (followRedirect(true)), AsyncHttpClient forwards 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.
Patches
Fixed in version 3.0.9. Users should upgrade immediately.
The fix 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.
Workarounds
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 because the Realm bypass still re-generates credentials.
Alternatively, disable redirect following (followRedirect(false)) and handle redirects manually with origin validation.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.asynchttpclient:async-http-client"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.0.9"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-40490"
],
"database_specific": {
"cwe_ids": [
"CWE-200"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-14T01:07:42Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Impact\nWhen redirect following is enabled (followRedirect(true)), AsyncHttpClient forwards 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.\n\nAdditionally, 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.\n\nAn 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.\n\n### Patches\nFixed in version 3.0.9. Users should upgrade immediately.\n\nThe fix 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.\n\n### Workarounds\nFor 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 because the Realm bypass still re-generates credentials.\n\nAlternatively, disable redirect following (followRedirect(false)) and handle redirects manually with origin validation.",
"id": "GHSA-cmxv-58fp-fm3g",
"modified": "2026-04-15T21:00:53Z",
"published": "2026-04-14T01:07:42Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/AsyncHttpClient/async-http-client/security/advisories/GHSA-cmxv-58fp-fm3g"
},
{
"type": "WEB",
"url": "https://github.com/AsyncHttpClient/async-http-client/commit/6b2fbb7f8"
},
{
"type": "PACKAGE",
"url": "https://github.com/AsyncHttpClient/async-http-client"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "AsyncHttpClient leaks authorization credentialsto untrusted domains on cross-origin redirects"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.