CVE-2026-40854
Last modified
CVE-2026-40854 is a high-severity vulnerability rated 8.7/10 on the CVSS scale. WNC T-Mobile 5G Box IDU router contains an authentication bypass vulnerability in the portal.cgi component. The session verification mechanism improperly validates the sessionid cookie by checking for the existence of a corresponding file in /tmp/login_user.
Description
WNC T-Mobile 5G Box IDU router contains an authentication bypass vulnerability in the portal.cgi component. The session verification mechanism improperly validates the sessionid cookie by checking for the existence of a corresponding file in /tmp/login_user. An attacker can bypass authentication by using directory entries such as "." or ".." in the cookie, allowing unauthorized access to the administration panel.This issue has been fixed in firmware version 1.1.0.651412
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| WNC | T-Mobile 5G Box IDU | < 1.1.0.651412 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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Scan your code nowSource: NVD / NIST