Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:P) | Attack requirements present |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:N) | No integrity impact |
| Availability (VA:N) | No availability impact |
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Schneider-Electric Ecostruxure Panel Server Pas400 Firmware
CVE-2026-6866 affects Schneider-Electric Ecostruxure Panel Server Pas400 Firmware, a product from Schneider-Electric. Before acting, confirm where Schneider-Electric Ecostruxure Panel Server Pas400 Firmware runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: CWE-1188 Initialization of a Resource with an Insecure Default vulnerability exists that could cause unauthorized disclosure of sensitive information when credentials revert to initial settings in rare circumstances, enabling unauthorized authentication using known credentials.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Schneider-Electric Ecostruxure Panel Server Pas400 Firmware |
| Affected versions | Ecostruxure Panel Server Pas400 Firmware before 002.006.000; Ecostruxure Panel Server Pas600 Firmware before 002.006.000; Ecostruxure Panel Server Pas600v2 Firmware before 002.006.000; Ecostruxure Panel Server Pas800 Firmware before 002.006.000; Ecostruxure Panel Server Pas800v2 Firmware before 002.006.000 |
| Published | May 12, 2026 |
| Last modified | Jun 24, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | cybersecurity@se.com |
How to detect it
- Inventory every instance of Schneider-Electric Ecostruxure Panel Server Pas400 Firmware and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Schneider-Electric Ecostruxure Panel Server Pas400 Firmware named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Schneider-Electric Ecostruxure Panel Server Pas400 Firmware to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
Technical References
Frequently asked questions
Related CVEs
CWE-78 Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability exists that could allow unauthorized execution of commands with elevated privileges, impacting system integrity, confidentiality, and availability when a privileged authenticated user interacts with a vulnerable network-exposed service.
CWE-476 NULL Pointer Dereference vulnerability exists that could cause a denial-of-service condition, rendering the device’s HMI and configuration functionality unavailable when malformed requests are received over exposed network interfaces.
CWE-522 Insufficiently Protected Credentials vulnerability that could cause unauthorized access and exposure of sensitive information when unauthenticated attacker accesses credentials stored within firmware or system files. With this credential an attacker could subsequently compromise the device if they have physical access to the device.
CWE-94: Improper Control of Generation of Code ('Code Injection') vulnerability exist that could cause execution of untrusted commands on the engineering workstation which could result in a limited compromise of the workstation and a potential loss of Confidentiality, Integrity and Availability of the subsequent system when an authenticated user opens a malicious project file.
CWE‑502: Deserialization of Untrusted Data vulnerability exists that could cause arbitrary code execution with administrative privileges when a locally authenticated attacker sends a crafted data stream, triggering unsafe deserialization.
CWE-416: Use After Free vulnerability that could cause remote code execution when the end user imports the malicious project file (SSD file) into Rapsody.
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