EUVD-2026-80055

| CVE-2026-76852 HIGH

Improper Validation of Integrity Check Value (CWE-354)

2026-09-15 disclosure@vulncheck.com

GHSA-6645-rfg8-rhrm

Authentication Bypass

8.7

CVSS 4.0 · Vendor: vulncheck

Severity by source

Vendor (vulncheck) PRIMARY

8.7 HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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

Primary rating from Vendor (vulncheck) · only source for this CVE.

CVSS VectorVendor: vulncheck

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Sep 15, 2026 - 22:31 vuln.today

CVE Published

Sep 15, 2026 - 22:16 cve.org

HIGH 8.7

DescriptionCVE.org

Netcore NR268 firmware version 1.7.121109 has an improper integrity verification flaw in mtd_write allowing forged firmware authenticity checks. Attackers can exploit put_file.cgi and check_image_uuid.c to bypass firmware signature validation and load unauthorized firmware images.

AnalysisAI

Netcore NR268 routers running firmware 1.7.121109 accept forged firmware images because the mtd_write flashing path does not properly validate the firmware authenticity check performed by check_image_uuid.c, allowing an attacker who can reach the upload endpoint (put_file.cgi) with low privileges to load unauthorized firmware. Successful exploitation gives an attacker full control over the device — high confidentiality, integrity and availability impact per the CVSS 4.0 vector (AV:N/AC:L/PR:L/UI:N) — and the malicious image persists across reboots. …