# CVE-2026-42019: Totolink X2000R stack-based buffer overflow in pppoe

Source: https://junglewise.ai/threats/cve-2026-42019-multiple-stack-based-buffer-overflow-vulnerabilities-exist-in-the  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-42019 · Severity: critical · CVSS 9.1 · Published 2026-10-20

The Totolink X2000R is a budget gigabit home router used primarily in eastern markets. Multiple stack-based buffer overflows in the pppoe DNS configuration parameters allow an authenticated attacker to achieve arbitrary code execution on the device, potentially compromising the network and all devices connected to it.

Technologies: [TOTOLINK X2000r](https://junglewise.ai/threats/technologies/x2000r). Vendors: [TOTOLINK](https://junglewise.ai/threats/vendors/totolink).

## Quick answers

**Is CVE-2026-42019 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42019 being exploited in the wild.

**How severe is CVE-2026-42019?** Critical severity, with a CVSS score of 9.1, published 20 October 2026.

**Which products and versions are affected?** TOTOLINK X2000r TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327.

**Is there a fix for CVE-2026-42019?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-42019 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-42019?** Check whether you run TOTOLINK X2000r at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

Stack-based buffer overflows exist in the boa web server's formIpv6Setup pppoe functionality, specifically in the pppoe_dns1 and pppoe_dns2 HTTP POST parameters (CVE-2026-42019 and CVE-2026-42020). These parameters are copied directly to the stack without bounds checking, allowing an authenticated user to overflow the buffer, overwrite the return address, and execute arbitrary code. The vulnerability requires authentication and a network-based HTTP request.

## Affected products

- Totolink X2000R TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327

## Timeline

- 2026-10-20: disclosed

## References

- [https://talosintelligence.com/vulnerability_reports/TALOS-2026-2394](https://talosintelligence.com/vulnerability_reports/TALOS-2026-2394)

## Related threats

- [TOTOLINK X2000R stack-based buffer overflow in formTR069Config](https://junglewise.ai/threats/cve-2026-9869-a-stack-based-buffer-overflow-vulnerability-exists-in-the-boa)
- [Totolink X2000R arbitrary file write in boa formUploadFile](https://junglewise.ai/threats/cve-2026-9827-a-arbitrary-file-write-vulnerability-exists-in-the-boa)
- [Totolink X2000R stack-based buffer overflow in boa formUploadFile](https://junglewise.ai/threats/cve-2026-9817-a-stack-based-buffer-overflow-vulnerability-exists-in-the-boa)
- [Totolink X2000R OS command injection in formWizard](https://junglewise.ai/threats/cve-2026-9814-an-os-command-injection-vulnerability-exists-in-the-boa-formwizard)
- [TOTOLINK X2000R stack-based buffer overflow in boa formFilter](https://junglewise.ai/threats/cve-2026-9660-multiple-exploitable-stack-based-buffer-overflow-vulnerabilities)