---
id: "CVE-2026-10136"
kind: "vulnerability"
aliases: ["CVE-2026-10136"]
title: "TOTOLink X2000R router: heap overflow in upload handler allows code execution"
severity: "critical"
cvss: 9.1
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "X2000R", "fixed": [], "affected": "TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327", "ecosystem": "firmware"}]
ecosystems: []
tags: ["embedded", "infrastructure", "router", "totolink", "x2000r"]
not_affected_if: ["auth-required", "other-firmware-versions", "wan-admin-disabled", "web-admin-disabled"]
published_at: "2026-10-20T21:17:16+00:00"
first_seen_at: "2026-10-23T21:57:21+00:00"
updated_at: "2026-10-23T23:18:02+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-10136", "first_seen_at": "2026-10-23T21:57:21+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T23:18:02+00:00"}]
---

# TOTOLink X2000R router: heap overflow in upload handler allows code execution

Heap overflow in the boa web server on the TOTOLINK X2000R. The filename in a multipart upload to /boafrm/formUpload (or formUploadFile) is copied with a length taken from the input itself, so it can overwrite the heap and run code. It needs an authenticated admin session (CVSS 9.1, PR:H). Talos disclosed it on 2026-10-20 after the vendor stayed silent. No fixed firmware is known.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- firmware:X2000R affected TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327 fixed ?

## How to check

In the router admin UI, open the firmware/status page and read the firmware version. TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327 is confirmed vulnerable; other builds are untested, so treat them as unknown. Also check whether remote/WAN web management is enabled, and whether the LAN is reachable by untrusted clients.

## Fix

No vendor fix published as of 2026-10-23 (checked Talos, CVE record). Mitigate: disable WAN/remote admin, set a strong unique admin password, restrict the admin UI to a trusted LAN host, and watch totolink.net for newer firmware.

## Timeline

- 2026-10-23T21:57:21+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-10136
- 2026-10-23T23:18:02+00:00 analyst — Talos TALOS-2026-2436 (primary) and CVE record read. Only build B20250421.1327 listed; no vendor fix found (vendor notified 2026-06-16, silent since ack 2026-06-25). No public PoC exploit, no exploitation seen, no X chatter. Siblings: CVE-2026-10138, 10135, 9660 same build. WAN exposure of admin UI not stated by sources.

## Documents

- [advisory] TALOS-2026-2436 Totolink X2000R boa formUpload() heap overflow https://talosintelligence.com/vulnerability_reports/TALOS-2026-2436
- [describes] CVE Record CVE-2026-10136 https://www.cve.org/CVERecord?id=CVE-2026-10136

## From the sources

A heap-based buffer overflow vulnerability exists in the boa formUpload() functionality of X2000R (version(s): TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327). A specially crafted HTTP request can lead to arbitrary code execution. An attacker can make an authenticated HTTP request to trigger this vulnerability.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_