# CVE-2026-121600: TOTOLINK A950RG MAC Filter cstecgi.cgi setMacFilterRules stack-based overflow

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

A flaw has been found in TOTOLINK A950RG 4.1.2cu.5268_B20221104. Affected by this vulnerability is the function setMacFilterRules of the file /cgi-bin/cstecgi.cgi of the component MAC Filter Handler. This manipulation of the argument addEffect causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been published and may be used.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- TOTOLINK / A950RG: 4.1.2cu.5268_B20221104 (affected). Source: CNA: VulDB

## Severity and prioritization

- CVSS 4.0: 9.4 (critical); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P; source: CNA: VulDB

- CVSS 3.1: 9.9 (critical); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 3.0: 9.9 (critical); CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 2.0: 9 (critical); AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR; source: CNA: VulDB

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-121, CWE-119

## Exploit evidence

- exploit: https://gist.github.com/H3rmesk1t/217c00b12e04fcde07c453a55579f808 (CNA: VulDB)

## References

- https://vuldb.com/vuln/430442 (CNA: VulDB; vdb-entry, technical-description)

- https://vuldb.com/vuln/430442/cti (CNA: VulDB; signature, permissions-required)

- https://vuldb.com/cve/CVE-2026-121600 (CNA: VulDB; third-party-advisory)

- https://vuldb.com/submit/1022562 (CNA: VulDB; third-party-advisory)

- https://gist.github.com/H3rmesk1t/217c00b12e04fcde07c453a55579f808 (CNA: VulDB; exploit)

- https://www.totolink.net/ (CNA: VulDB; product)

## Provenance

- CNA: VulDB: https://www.cve.org/CVERecord?id=CVE-2026-121600; retrieved 2026-11-04; source updated 2026-11-04

Revision: 1c6b0bf95de40694352dfebc8ec612387842d8152cb9fef97429c751d070a64f

Canonical: https://y2.dev/cve/CVE-2026-121600

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