Information disclosure in Async-http-client - CVE-2026-40490
Published: April 14, 2026
Vulnerability identifier: #VU125944
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-40490
CWE-ID: CWE-200
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to exposure of sensitive information in redirect handling when following cross-origin redirects. A remote attacker can control a redirect target to disclose sensitive information.
The issue can leak Authorization and Proxy-Authorization headers as well as Realm credentials, including during HTTPS-to-HTTP downgrades. Even when authorization stripping is enabled, plaintext Realm credentials may still be propagated and regenerated for Basic and Digest authentication schemes.
Affected software
Async-http-client
How to mitigate CVE-2026-40490
Install security update from vendor's website.
Async-http-client - update to 3.0.9