CVE-2025-3898 Overview
CVE-2025-3898 is an improper input validation vulnerability [CWE-20] affecting a Schneider Electric webserver component. An authenticated attacker can trigger a Denial of Service (DoS) condition by sending an HTTPS request that contains an invalid data type to the target webserver. Successful exploitation disrupts the availability of the affected service without requiring user interaction. The flaw was disclosed through Schneider Electric security advisory SEVD-2025-161-02.
Critical Impact
Authenticated attackers on the network can crash the affected webserver by submitting a malformed HTTPS request, interrupting availability of the managed device or service.
Affected Products
- Schneider Electric product referenced in advisory SEVD-2025-161-02 (see vendor notice for exact models and firmware ranges)
Discovery Timeline
- 2025-06-10 - CVE-2025-3898 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-3898
Vulnerability Analysis
The vulnerability arises in the HTTPS request handling logic of the affected Schneider Electric webserver. The webserver accepts request parameters without validating that each field matches the expected data type. When an authenticated user submits a request that contains a value of an unexpected type, the server fails to handle the condition gracefully and enters an error state that terminates or hangs the webserver process.
Because the webserver typically fronts management and configuration interfaces on industrial devices, a loss of availability translates to loss of monitoring and administrative access. The attack requires valid credentials but no user interaction and is exploitable over the network with low complexity. See the Schneider Electric Security Notice SEVD-2025-161-02 for authoritative product and version details.
Root Cause
The root cause is improper input validation [CWE-20] in the HTTPS request parsing path. Request fields are consumed without strict type checking, allowing invalid data types to propagate into code paths that assume well-formed input. The resulting unhandled condition crashes or hangs the webserver.
Attack Vector
Exploitation requires network reachability to the webserver and valid low-privilege credentials. The attacker crafts an HTTPS request in which one or more parameters use an unexpected data type, then sends it to the webserver endpoint. The malformed request triggers the failure and produces a Denial of Service condition affecting availability only.
No verified proof-of-concept code has been published. Refer to the vendor advisory for detailed exploitation prerequisites and impacted endpoints.
Detection Methods for CVE-2025-3898
Indicators of Compromise
- Unexpected restarts, hangs, or crashes of the Schneider Electric device webserver process.
- HTTPS requests from authenticated sessions containing malformed or type-mismatched parameters preceding a service outage.
- Loss of management-plane availability while the underlying device continues operating.
Detection Strategies
- Inspect HTTPS traffic to affected webservers for requests containing parameters that violate the documented API schema.
- Correlate authenticated user sessions with subsequent webserver availability failures to identify abuse patterns.
- Enable verbose webserver logging on affected devices where supported, and forward logs to a centralized SIEM for anomaly analysis.
Monitoring Recommendations
- Monitor uptime and health of Schneider Electric device webservers with active availability checks.
- Alert on repeated authentication events followed by HTTP 5xx responses or session terminations.
- Track configuration or management interface outages across OT assets and correlate with recent user activity.
How to Mitigate CVE-2025-3898
Immediate Actions Required
- Review Schneider Electric advisory SEVD-2025-161-02 to identify affected products and firmware versions in your environment.
- Apply vendor-provided firmware or software updates to all affected devices as soon as they are available.
- Restrict network access to the device webserver to trusted management networks and hosts only.
- Rotate and audit credentials with access to affected webserver interfaces to reduce the pool of accounts that could exploit the flaw.
Patch Information
Schneider Electric has published remediation guidance in security notice SEVD-2025-161-02. Consult the advisory for fixed firmware or software versions, upgrade instructions, and product-specific compensating controls.
Workarounds
- Place affected devices behind a firewall or management VLAN that permits HTTPS only from authorized administrator workstations.
- Enforce least privilege on webserver accounts and remove unused or shared credentials.
- Deploy network segmentation between OT and IT networks to limit the blast radius of a DoS condition.
- Monitor for and automatically restart failed webserver services where the platform supports it, to shorten recovery time.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
