Copeland XWEB 300D PRO: Unexpected Status Code or Return Value
CVE-2026-25085 is a critical-severity unexpected status code or return value vulnerability in Copeland XWEB 300D PRO from Copeland, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Copeland XWEB 300D PRO versions: 1.12.1 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Copeland XWEB 300D PRO you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Copeland | Copeland XWEB 300D PRO | 1.12.1 and earlier | Not stated |
| Copeland | Copeland XWEB 500D PRO | 1.12.1 and earlier | Not stated |
| Copeland | Copeland XWEB 500B PRO | 1.12.1 and earlier | Not stated |
| Copeland | Xweb 500b Pro Firmware | 1.12.1 and earlier | Not stated |
| Copeland | Xweb 300d Pro Firmware | 1.12.1 and earlier | Not stated |
| Copeland | Xweb 500d Pro Firmware | 1.12.1 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.6 | High | CNA (hq.dhs.gov) |
| CVSS 3.1 | 9.8 | Critical | NVD |
Official description
A vulnerability exists in Copeland XWEB Pro version 1.12.1 and prior, in which an unexpected return value from the authentication routine is later on processed as a legitimate value, resulting in an authentication bypass.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Unexpected Status Code or Return Value
The product does not properly check when a function or operation returns a value that is legitimate for the function, but is not expected by the product.
More Unexpected Status Code or Return Value vulnerabilities (CWE-394)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-10.jsonThird Party Advisory
- cisa.gov/news-events/ics-advisories/icsa-26-057-10Third Party Advisory, US Government Resource
Other references
Other vulnerabilities in Copeland XWEB 300D PRO
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
Recent Unexpected Status Code or Return Value vulnerabilities
- 7.3 High severity
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