CVE-2026-76870
HIGHCVE-2026-76870 is a high-severity (CVSS 7.1) Out-of-bounds Read vulnerability. O3 Security confirms whether CVE-2026-76870 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
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…
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-76870 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-76870 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-76870. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-76870 in your dependencies?
O3 detects CVE-2026-76870 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.