# CVE-2026-76870

## Summary

- **CVE ID:** CVE-2026-76870
- **Severity:** HIGH
- **CVSS Score:** 7.1 (CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-125
- **Published:** Sep 15, 2026
- **Last Modified:** Sep 16, 2026

## Description

Netcore NR255-V version 1.5.130703 contains an out-of-bounds read vulnerability in the mtd_write pre-flash validation routine triggered by short firmware uploads. Attackers can upload a truncated firmware image via put_file_cgi.c to trigger out-of-bounds reads across main.c, check_image_uuid.c, and oemMD5Update.c.

## Affected Products

- Netcore — NR255-V (1.5.130703)

## References

- [CNA](https://github.com/draw-ctf/netcore-router-public-refs/blob/main/2026.08.19-netcore-nr255v-firmware-upload-oob.md)
- [CNA](https://www.vulncheck.com/advisories/netcore-nr255-v-1.5.130703-out-of-bounds-read-in-mtd-write-firmware-upload-validation)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.31%
- **EPSS Percentile:** 24.3

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._