Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Scope (S:C) | Scope changed: impact spreads beyond the component |
| Confidentiality (C:H) | High confidentiality impact |
| Integrity (I:H) | High integrity impact |
| Availability (A:H) | High availability impact |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
About Copeland Xweb 300d Pro Firmware
CVE-2026-21718 affects Copeland Xweb 300d Pro Firmware, a product from Copeland. Before acting, confirm where Copeland Xweb 300d Pro 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: An authentication bypass vulnerability exists in Copeland XWEB Pro version 1.12.1 and prior, enabling any attackers to bypass the authentication requirement and achieve pre-authenticated code execution on the system.
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 | Copeland Xweb 300d Pro Firmware |
| Affected versions | Xweb 300d Pro Firmware up to and including 1.12.1; Xweb 500d Pro Firmware up to and including 1.12.1; Xweb 500b Pro Firmware up to and including 1.12.1 |
| Published | Feb 27, 2026 |
| Last modified | Jun 17, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | ics-cert@hq.dhs.gov |
How to detect it
- Inventory every instance of Copeland Xweb 300d Pro 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 Copeland Xweb 300d Pro 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 Copeland Xweb 300d Pro 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
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by modifying malicious input injected into the MBird SMS service URL and/or code via the utility route which is later processed during system setup, leading to remote code execution.
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by injecting malicious input into the server username and/or password fields of the restore action in the API V1 route.
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by injecting malicious input into the Wi-Fi SSID and/or password fields can lead to remote code execution when the configuration is processed.
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by injecting malicious input into parameters of the Modbus command tool in the debug route.
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by configuring a maliciously crafted LCD state which is later processed during system setup, enabling remote code execution.
An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by supplying a crafted template file to the devices route.
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