WNC T-Mobile 5G Box IDU router is vulnerable to improper access control. The vulnerability exists in the wnc_maccheck.cgi endpoint, which is accessible without authentication. It allows a remote attacker to retrieve sensitive configuration data, including the administrator web password, WiFi passphrase, and technical device information.This issue has been fixed in firmware version 1.1.0.651412
CVE-2026-40856
This high-severity CVE scores 7.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 75% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.1
- EG Score
- 7.1(medium)
- EG Risk
- 32(Track)EG Risk 32/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity71% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 25%
- KEV
- Not listed
Published
September 16, 2026
Last Modified
September 16, 2026
Advisory Details (1)
Auto-updated Sep 16, 2026Podatności w routerach WNC T-Mobile 5G Box IDU | CERT Polska
https://cert.pl/posts/2026/09/CVE-2026-40854Vendor Advisories for CVE-2026-40856(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 24× in last 7d / 24× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-21 00:45 UTCEG score recompute
- 2026-09-21 00:45 UTCGHSA enrichment
- 2026-09-20 20:15 UTCEPSS rescore
- 2026-09-20 13:32 UTCGHSA enrichment
- 2026-09-20 02:20 UTCEG score recompute
- 2026-09-20 02:20 UTCGHSA enrichment
- 2026-09-19 15:08 UTCGHSA enrichment
- 2026-09-19 03:55 UTCEG score recompute
- 2026-09-19 03:55 UTCGHSA enrichment
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 16:43 UTCGHSA enrichment
- 2026-09-18 05:31 UTCEG score recompute
- 2026-09-18 05:31 UTCGHSA enrichment
- 2026-09-17 19:31 UTCEPSS rescore
- 2026-09-17 18:19 UTCGHSA enrichment
- 2026-09-17 06:40 UTCGHSA enrichment
- 2026-09-16 19:25 UTCGHSA enrichment
- 2026-09-16 17:42 UTCEG score recompute
- 2026-09-16 17:42 UTCGHSA enrichment
- 2026-09-16 16:35 UTCEG score recompute
- 2026-09-16 16:35 UTCGHSA enrichment
- 2026-09-16 12:22 UTCEG score recompute
- 2026-09-16 11:32 UTCEG score recompute
- 2026-09-16 11:30 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Same CWE
10 shownCWE-306
Frequently asked(5)
What is CVE-2026-40856?
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What is the CVSS score of CVE-2026-40856?
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-40856
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