TOTOLINK X2000R: Heap-based buffer overflow in boa formUpload()
Summary
A heap-based buffer overflow in the formUpload() function of the boa web server on the TOTOLINK X2000R router allows an attacker to execute arbitrary code on the device. The attacker needs valid administrator credentials, because the flaw is triggered by an authenticated HTTP request. Successful exploitation would give full control over a router at the network edge, which could be used to intercept or redirect traffic.
Affected
- TOTOLINK X2000R, firmware TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327 (the only version listed by Talos and the CNA)
- Other firmware versions: Unknown.
Fixed in
Unknown. No fixed firmware version has been published in the sources checked.
Workaround
- Do not expose the web administration interface to the internet; restrict it to the LAN and disable remote management.
- Change default administrator credentials and limit who has admin access.
Exploitation
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
- No public proof of concept found in the sources checked; this does not rule out that one exists.
- Authentication is required.
Our recommendation
- Verify whether the X2000R is in use and check the exact firmware build.
- Confirm that the web administration interface is not reachable from the internet and rotate administrator passwords.
- Monitor TOTOLINK for a fixed firmware and update when one is available.
- If no fix is published or the device is end-of-life, plan replacement.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Cisco Talos TALOS-2026-2436 talosintelligence.com
- OpenCVE CVE-2026-10136 app.opencve.io
- Strix CVE-2026-10136 www.strix.ai
- Vulners Talos TALOS-2026-2436 vulners.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 06:07.
Original description (NVD)
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.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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