CVE-2026-85720
Description
A flaw was found in the AsyncHttpClient library. When a Java application uses an HTTP proxy to connect to an HTTPS origin, the library sends sensitive origin credentials, such as Basic, Digest, NTLM, Kerberos, or SPNEGO tokens, in the plaintext CONNECT request. This occurs before a secure TLS (Transport Layer Security) tunnel is established, allowing the proxy and any network observers on the client-to-proxy connection to view these credentials. This vulnerability leads to information disclosure of sensitive user authentication data.
Statement
This vulnerability is rated as having Moderate impact because credential interception requires a specific deployment configuration where client requests are routed through an outbound HTTP proxy while utilizing preemptive origin authentication. An attacker must either control the intermediary proxy server or occupy a privileged network position on the unencrypted client-to-proxy hop before TLS encapsulation occurs. Deployments that connect directly to target services without an unencrypted proxy hop or operate across trusted internal networks face significantly reduced risk.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.9 | N/A | 5.9 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Understanding the Weakness (CWE)
Integrity,Confidentiality
Technical Impact: Read Application Data; Modify Files or Directories
Anyone can read the information by gaining access to the channel being used for communication. Many communication channels can be "sniffed" (monitored) by adversaries during data transmission. For example, in networking, packets can traverse many intermediary nodes from the source to the destination, whether across the internet, an internal network, the cloud, etc. Some actors might have privileged access to a network interface or any link along the channel, such as a router, but they might not be authorized to collect the underlying data. As a result, network traffic could be sniffed by adversaries, spilling security-critical data.
Integrity,Confidentiality
Technical Impact: Read Application Data; Modify Files or Directories; Other
When full communications are recorded or logged, such as with a packet dump, an adversary could attempt to obtain the dump long after the transmission has occurred and try to "sniff" the cleartext from the recorded communications in the dump itself. Even if the information is encoded in a way that is not human-readable, certain techniques could determine which encoding is being used, then decode the information.
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