Cleartext transmission of sensitive information in Async-http-client - #VU142446
Published: August 13, 2026
Vulnerability identifier: #VU142446
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: N/A
CWE-ID: CWE-319
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 cleartext transmission of sensitive information in the HTTP proxy request line handling in Async-http-client when routing plaintext HTTP requests through an HTTP proxy using a URL that contains userinfo credentials. A remote attacker can route or observe a specially crafted request to disclose sensitive information.
The issue affects only the HTTP/1.1 absolute-form proxy request target and can expose embedded URL credentials to the proxy and to observers of the client-to-proxy hop.
Affected software
Async-http-client
Remediation
Install security update from vendor's website.
Async-http-client - addressed in versions 2.16.1, 3.0.12