Linux Distros Unpatched Vulnerability : CVE-2026-64684

medium Nessus Plugin ID 346886

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- RMCP is an official Rust SDK for the Model Context Protocol. Prior to 2.1.0, the rmcp crate's StreamableHttpClientTransport in crates/rmcp/src/transport/common/reqwest/streamable_http_client.rs builds its default_http_client with reqwest's automatic redirect policy and applies caller-supplied values from StreamableHttpClientTransportConfig.custom_headers without marking them as sensitive. When a malicious or compromised MCP endpoint returns a cross-origin 307 or 308 redirect, reqwest follows the redirect and apply_custom_headers causes custom API keys or authentication tokens to be replayed to the new origin, where an attacker can capture and reuse them. The separate auth_header path is not affected because it uses the standard Authorization header, which reqwest strips on cross-origin redirects. This issue is fixed in version 2.1.0. (CVE-2026-64684)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2026-64684

Plugin Details

Severity: Medium

ID: 346886

File Name: unpatched_CVE_2026_64684.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 9/17/2026

Updated: 9/18/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.3

Percentile: 50.57

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:N/A:N

CVSS Score Source: CVE-2026-64684

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 6.2

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:10, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:redhat:enterprise_linux:goose

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 9/16/2026

Reference Information

CVE: CVE-2026-64684