CVE-2026-9073: Foreman MCP Server Info Disclosure Flaw

CVE-2026-9073 Overview

CVE-2026-9073 is an information disclosure vulnerability in foreman-mcp-server that exposes sensitive authentication data through container logs. The component uses two logging mechanisms that mishandle credentials. The first writes session identifiers, which function as authentication credentials, at the informational log level. The second mechanism, active when debug logging is enabled, applies incomplete sanitization to HTTP request headers and writes authorization tokens and API keys in cleartext. An attacker with local access to log files, or to a centralized log aggregation platform receiving these logs, can harvest valid credentials and replay them against the Foreman management interface. The weakness is tracked under CWE-532: Insertion of Sensitive Information into Log File.

Critical Impact
Session identifiers, authorization tokens, and API keys are persisted in plaintext within container logs, enabling credential theft and session replay against Foreman-managed infrastructure.

Affected Products

foreman-mcp-server (Red Hat distribution)
Red Hat products bundling the affected component as referenced in RHSA-2026:28438
Environments forwarding container logs to centralized SIEM or log aggregation platforms

Discovery Timeline

2026-06-23 - CVE-2026-9073 published to NVD
2026-06-25 - Last updated in NVD database

Technical Details for CVE-2026-9073

Vulnerability Analysis

The vulnerability resides in the logging subsystem of foreman-mcp-server, the Model Context Protocol server component integrated with the Foreman lifecycle management platform. Two independent code paths write authentication material to logs.

The first path emits session identifiers at the INFO log level. Foreman treats these session identifiers as bearer credentials, so any actor who reads the log obtains a usable authentication token until the session expires.

The second path is reached when debug-level logging is enabled. The server attempts to redact sensitive HTTP request headers before logging them, but the sanitization routine misses several header names used for authentication, including Authorization and custom API key headers. As a result, raw bearer tokens and API keys appear verbatim in debug output.

Root Cause

The root cause is improper output neutralization in the logger. The session identifier code path classifies session IDs as non-sensitive routing metadata rather than credentials. The debug-mode header sanitizer uses an incomplete denylist of header names instead of an allowlist or case-insensitive credential-aware filter. Both flaws fall under CWE-532.

Attack Vector

Exploitation requires local access to the log destination. An attacker with read access to the container's standard output stream, the underlying log files, or a centralized logging platform that ingests these logs can extract credentials. No authentication to the Foreman application itself is required to read the logs once they leak. Recovered session tokens and API keys can then be replayed to the Foreman API to perform actions as the legitimate user.

No public proof-of-concept exploit code is available. The vulnerability is described in prose in the Red Hat advisory and Bugzilla #2480151.

Detection Methods for CVE-2026-9073

Indicators of Compromise

Log entries from foreman-mcp-server containing session identifier values at the INFO level
Debug log lines containing Authorization: Bearer or API key header values in cleartext
Unexpected reuse of session tokens from IP addresses that did not originate the session
Access to log storage paths or log aggregation indexes by accounts outside the logging operations team

Detection Strategies

Scan existing foreman-mcp-server logs with regular expressions matching bearer tokens, session cookie patterns, and known API key formats
Correlate Foreman API authentication events with the source IPs of users who hold read access to log aggregation platforms
Alert on debug-level logging being enabled in production deployments of foreman-mcp-server

Monitoring Recommendations

Monitor log forwarder configurations for routes that ship foreman-mcp-server output to multi-tenant or broadly accessible indexes
Track query activity on SIEM indexes containing the affected logs and flag searches for Authorization, Bearer, or session cookie names
Audit access control lists on container log volumes, persistent log directories, and downstream log analytics tooling

How to Mitigate CVE-2026-9073

Immediate Actions Required

Apply the update referenced in RHSA-2026:28438 to all instances of foreman-mcp-server
Disable debug logging on foreman-mcp-server in production until the patched version is deployed
Rotate all Foreman API keys, service tokens, and active session identifiers that may have been written to logs
Purge or quarantine historical log data that contains the leaked credential material

Patch Information

Red Hat has released a fixed package through RHSA-2026:28438. Tracking information is available in the Red Hat CVE record and Bugzilla #2480151. Administrators should update foreman-mcp-server to the version specified in the erratum and restart the service.

Workarounds

Restrict the log level of foreman-mcp-server to WARN or ERROR to suppress the INFO-level session identifier output and disable the vulnerable debug header path
Tighten filesystem permissions on container log directories so only the logging service account can read them
Configure log forwarders to drop or redact fields matching Authorization, Cookie, and known API key header patterns before shipping to centralized platforms
Segment log aggregation indexes containing foreman-mcp-server data and limit query access to a least-privilege group

bash

# Example forwarder redaction rule (Fluent Bit) applied before shipping logs
[FILTER]
    Name    modify
    Match   foreman.mcp.*
    Remove_wildcard Authorization
    Remove_wildcard Cookie
    Remove_wildcard X-Api-Key