# CVE-2026-121599: TOTOLINK A950RG Multi-SSID Configuration cstecgi.cgi delWiFiMultipleConfig stack-based overflow

- Exploited (CISA KEV): no
- Published: 2026-11-04
- CVSS: 9.4 CRITICAL (v4.0)
- EPSS: no score
- CWE: CWE-121, CWE-119

A vulnerability was detected in TOTOLINK A950RG 4.1.2cu.5268_B20221104. Affected is the function setWiFiMultipleConfig/delWiFiMultipleConfig of the file /cgi-bin/cstecgi.cgi of the component Multi-SSID Configuration. The manipulation of the argument wepkey2/wepkey3 results in stack-based buffer overflow. It is possible to launch the attack remotely. The exploit is now public and may be used.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | No public claim | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | No public claim | — | — |
| Fastly | No public claim | — | — |
| Vercel | No public claim | — | — |
| F5 | No public claim | — | — |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

## Social

2 posts seen since 2026-11-04.

- mastodon 2026-11-04: TOTOLINK A950RG 4.1.2cu.5268_B20221104 hit by CRITICAL stack buffer overflow (CVE-2026-121599, CVSS 9.9). Exploitable via /cgi-bin/cstecgi.cgi — remote code execution possible. No patch yet; isolate devices. Public exploit out. https:// radar.offseq.com/threat/a-vuln erability-w… (https://infosec.exchange/@offseq/117556644171552757)
- bluesky 2026-11-04: CVE-2026-121599 CRITICAL (CVSS 9.9) A vulnerability was detected in TOTOLINK A950RG 4.1.2cu.5268_B20221104 Fix: https://patchthecve.com/cve/CVE-2026-121599.html (https://bsky.app/profile/patchthecve.bsky.social/post/3mzh6fiicad2y)

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2026-121599 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2026-121599