CVE-2024-35206 Overview
CVE-2024-35206 affects Siemens SINEC Traffic Analyzer (6GK8822-1BG01-0BA0), an industrial network monitoring appliance. The affected application does not expire user sessions, allowing reuse of authenticated session tokens after they should have been invalidated. An attacker with access to a stale session identifier can obtain unauthorized access to the application without re-authenticating. The flaw is categorized as Insufficient Session Expiration [CWE-613]. Siemens addressed the issue in version V1.2.
Critical Impact
Sessions remain valid beyond their intended lifetime, enabling unauthorized access to the SINEC Traffic Analyzer management interface using previously captured or shared session tokens.
Affected Products
- Siemens SINEC Traffic Analyzer (6GK8822-1BG01-0BA0) — all versions prior to V1.2
- Siemens industrial network monitoring deployments using the affected article number
- Operational technology (OT) environments relying on SINEC Traffic Analyzer for traffic visibility
Discovery Timeline
- 2024-06-11 - CVE-2024-35206 published to the National Vulnerability Database (NVD)
- 2024-06-11 - Siemens publishes Siemens Security Advisory SSA-196737
- 2025-02-11 - Last updated in NVD database
Technical Details for CVE-2024-35206
Vulnerability Analysis
The vulnerability arises from improper session lifecycle management in the SINEC Traffic Analyzer web application. Authenticated sessions are not invalidated based on a fixed expiration window or idle timeout. A session identifier issued at authentication remains usable until the server is manually restarted or the user explicitly logs out.
This behavior conflicts with standard session management requirements for industrial management interfaces. Long-lived session tokens broaden the window for token theft, replay, and unauthorized administrative actions on a sensor that observes sensitive OT network traffic.
The CVSS v4.0 vector indicates a local attack vector with high impact on confidentiality and integrity. Exploitation does not require user interaction or privileges, but the attacker must obtain a valid session token from the local environment, such as through a compromised workstation, shared terminal, or recovered browser artifacts.
Root Cause
The root cause is the absence of server-side session expiration logic. The application issues session identifiers without an absolute timeout, idle timeout, or revocation tied to authentication state changes, violating CWE-613 (Insufficient Session Expiration).
Attack Vector
An attacker who recovers a previously issued session token, for example from a shared kiosk, browser storage, captured proxy logs, or an unattended administrator session, can present that token to the SINEC Traffic Analyzer web interface and inherit the original user's authenticated context. No additional credentials are required.
No public proof-of-concept code or weaponized exploit has been published for CVE-2024-35206. See the Siemens Security Advisory SSA-196737 for vendor technical details.
Detection Methods for CVE-2024-35206
Indicators of Compromise
- Authenticated SINEC Traffic Analyzer activity from a session token after the legitimate user has logged off or left the console
- Repeated reuse of the same session cookie across multiple source IP addresses or user agents
- Administrative configuration changes occurring outside maintenance windows without a preceding authentication event in logs
- Long-lived sessions persisting across days or weeks against a single account
Detection Strategies
- Correlate authentication events with session activity timestamps to identify sessions used beyond reasonable working hours or after user logoff
- Inspect web server and reverse proxy logs for the same session identifier presented from differing client fingerprints (IP, user agent, TLS fingerprint)
- Alert on access to the SINEC Traffic Analyzer management interface from hosts that are not approved administrative jump servers
- Behavioral analytics on endpoints used to administer the appliance can surface credential theft and browser artifact exfiltration that precedes session reuse
Monitoring Recommendations
- Forward SINEC Traffic Analyzer access logs and any upstream reverse proxy logs to a centralized SIEM or data lake for retention and correlation
- Monitor administrator workstations for unauthorized access to browser session storage and cookie databases
- Establish a baseline for normal session duration per administrator and alert on outliers
How to Mitigate CVE-2024-35206
Immediate Actions Required
- Upgrade SINEC Traffic Analyzer (6GK8822-1BG01-0BA0) to version V1.2 or later as published in Siemens Security Advisory SSA-196737
- Force logoff of all current users and invalidate existing sessions immediately after upgrade
- Rotate administrative credentials used to access the appliance prior to the patch
- Restrict network access to the management interface to a dedicated administrative VLAN or jump host
Patch Information
Siemens has released SINEC Traffic Analyzer V1.2, which addresses the session expiration defect. Refer to Siemens Security Advisory SSA-196737 for download instructions and version verification.
Workarounds
- Manually log out of the SINEC Traffic Analyzer web interface at the end of every session rather than closing the browser tab
- Restart the appliance on a scheduled basis to invalidate residual sessions where operationally acceptable
- Limit administrative access to dedicated, hardened workstations with full disk encryption and endpoint protection to reduce session token theft risk
- Place the management interface behind a reverse proxy that enforces its own session timeout policy until the patch can be applied
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
