CVE-2026-31181

Remote Command Execution via STUN Server Address Injection in Totolink A3300R Firmware

Published Apr 23, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Description
An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the stunServerAddr parameter to /cgi-bin/cstecgi.cgi.

Analysis

AI-generated

Technical impact

An OS command injection flaw exists in Totolink A3300R firmware through the stunServerAddr parameter in /cgi-bin/cstecgi.cgi, allowing a remote attacker to execute arbitrary commands. This flaw, classified as CWE‑78, can compromise confidentiality, integrity, and availability of affected devices because code runs with the device’s privileges. Based on the description, it is inferred that exploitation would compromise those aspects.

Affected Systems

The vulnerability is present in Totolink A3300R routers running firmware version 17.0.0cu.557_B20221024. No other versions are reported affected. The affected product is the Totolink A3300R, a home‑network router.

Risk and Exploitability

The CVSS score of 9.8 indicates critical severity, while the EPSS score of <1% suggests low current exploitation probability, yet the existence of a remote command execution avenue makes it highly damaging if exploited. The vulnerability is not listed in the CISA KEV catalog. Based on the description, the likely attack vector is a remote attacker sending a crafted HTTP request with a malicious stunServerAddr value to the router.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply any firmware update for the Totolink A3300R that addresses the command injection issue.
  • Configure the router’s firewall or access control lists to restrict HTTP access to /cgi-bin/cstecgi.cgi to trusted IP addresses only.
  • Disable or block external STUN traffic and the stunServerAddr parameter to prevent injection of malicious commands.

Generated by OpenCVE AI on April 28, 2026 at 15:09 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Title Remote Command Execution via STUN Server Address Injection in Totolink A3300R Firmware
Type Values Removed Values Added
First Time appeared Totolink
Totolink a3300r
Totolink a3300r Firmware
CPEs cpe:2.3:h:totolink:a3300r:-:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a3300r_firmware:17.0.0cu.557_b20221024:*:*:*:*:*:*:*
Vendors & Products Totolink
Totolink a3300r
Totolink a3300r Firmware
Type Values Removed Values Added
Weaknesses CWE-78
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the stunServerAddr parameter to /cgi-bin/cstecgi.cgi.
References
Weaknesses
  • CWE-78

    Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Apr 23, 2026, 6:34 PM
Reserved
Mar 9, 2026, 12:00 AM
Status
Analyzed
Published
Apr 23, 2026, 6:16 PM
Modified
Nov 11, 2026, 7:10 PM