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CriticalCISA KEVExploited in the wild7 public exploits

Palo Alto PAN-OS User-ID Authentication Portal Buffer Overflow RCE

CVE-2026-0300 is a critical out-of-bounds write / buffer overflow vulnerability in the User-ID Authentication Portal service of Palo Alto Networks PAN-OS, also referred to as the Captive Portal. By sending specially crafted packets to the vulnerable portal, an unauthenticated remote attacker can trigger memory corruption and achieve arbitrary code execution with root privileges on affected PA-Series and VM-Series firewalls. Public reporting and vendor-linked summaries indicate the vulnerable component is exposed through the User-ID Authentication Portal service and that exploitation has been observed in the wild, including post-exploitation shellcode injection into an nginx worker process. Prisma Access, Cloud NGFW, and Panorama are reported as not affected.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. For analysts and engineers who need to decide and keep moving.

Impact

What an attacker gets — and what they’ve been doing with it.

Successful exploitation yields unauthenticated remote code execution as root on a network-edge firewall. This gives an attacker full control of the affected appliance, including the ability to execute arbitrary commands, alter configuration, bypass or subvert security policy enforcement, access or manipulate traffic traversing the device, steal credentials or service-account material present on the firewall, pivot into internal networks, and destroy forensic evidence. Reporting on observed exploitation also indicates use for shellcode injection, Active Directory enumeration, tunneling/proxy deployment, and log/crash-artifact deletion to reduce visibility.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, disable the User-ID Authentication Portal/Captive Portal if it is not required. If it must remain enabled, restrict access to only trusted internal IP addresses or trusted zones and ensure it is not reachable from the public internet or other untrusted networks. Multiple reports also cite Palo Alto guidance to disable Response Pages in Interface Management Profiles attached to L3 interfaces where untrusted or internet traffic can ingress. Organizations should monitor vendor advisories, review KEV-driven urgency, inspect exposed PAN-OS devices for signs of compromise, and prioritize forensic review of internet-facing PA-Series and VM-Series systems with the portal enabled.

Remediation

Patch, then assume compromise.

Upgrade PAN-OS to a fixed release in the affected train. Reported fixed versions/build thresholds include: PAN-OS 12.1 to 12.1.4-h5 or later, and 12.1.7 or later; PAN-OS 11.2 to 11.2.4-h17 or later, 11.2.7-h13 or later, 11.2.10-h6 or later, and 11.2.12 or later; PAN-OS 11.1 to 11.1.4-h33 or later, 11.1.6-h32 or later, 11.1.7-h6 or later, 11.1.10-h25 or later, 11.1.13-h5 or later, and 11.1.15 or later; PAN-OS 10.2 to 10.2.7-h34 or later, 10.2.10-h36 or later, 10.2.13-h21 or later, 10.2.16-h7 or later, and 10.2.18-h6 or later. Apply the vendor-designated patch appropriate to the deployed release train and verify the User-ID Authentication Portal exposure after upgrade.
PUBLIC EXPLOITS

Exploits

3 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (4 hidden).

VALID 3 / 7 TOTALView all
CVE-2026-0300-POCMaturityPoCVerified exploit

This repository is a small standalone Python proof-of-concept consisting of one README and one executable script, research_poc.py. The script is the sole exploit implementation and uses only Python standard libraries (socket, struct, argparse, sys, time). It presents itself as a PoC for CVE-2026-0300 affecting Palo Alto Networks PAN-OS User-ID / captive portal functionality. Exploit flow: the script accepts a target IP, target port, callback IP/port, overflow offset, and return address. It generates hardcoded Linux x64 reverse shell shellcode, dynamically embedding the operator-provided LHOST and LPORT. It then constructs an overflow buffer as padding + packed return address + NOP sled + shellcode, wraps that buffer in an HTTP POST request to /php/login.php, and sends it over a raw TCP socket to the target service (default port 6082). The intended outcome is unauthenticated remote code execution followed by a reverse shell callback to the attacker. Main capabilities: unauthenticated network delivery of a crafted exploit request, configurable overflow parameters (offset and return address), and embedded reverse shell payload generation. This is not a scanner or detector; it is an active exploitation script. The payload is basic and partly customizable through CLI arguments, but the shellcode type is fixed, so the repository is best classified as OPERATIONAL rather than weaponized. Repository structure is minimal: README.md documents the claimed vulnerability, affected PAN-OS versions, usage syntax, and mitigation guidance; research_poc.py contains the full exploit logic and CLI entry point. No framework affiliation, auxiliary modules, persistence logic, or post-exploitation tooling are present.

p3Nt3st3r-sTArDisclosed May 6, 2026markdownpythonnetworkweb
CVE-2026-0300-PANOSMaturityPoCVerified exploit

The repository is a small standalone PoC consisting of one Python exploit script (Poc.py) and two Markdown documents (README.md and docs/VULNERABILITY.md). The only executable code is Poc.py, which uses Python's socket and struct modules to build a raw HTTP POST request and send it directly to a target host. The script accepts a target host, port, overflow offset, and return address. It constructs a payload of repeated 'A' bytes, appends a little-endian 64-bit return address, then adds a short NOP sled and 0xCC breakpoint bytes as placeholder shellcode. This indicates a proof-of-concept for memory corruption / buffer overflow testing rather than a complete weaponized RCE exploit. Notably, the exploit code targets POST /php/login.php on a default port of 6082, while the documentation claims the vulnerability affects Palo Alto Networks PAN-OS User-ID Portal and references port 5007 and other paths such as /sslvpn/logout and /api/endpoint. That mismatch suggests the documentation and code are not well aligned, reducing confidence that the PoC accurately implements the described PAN-OS vulnerability. Still, the script is clearly exploit-oriented: it delivers a crafted network payload intended to overwrite control flow and potentially execute attacker-controlled bytes. Capabilities: network-based unauthenticated delivery of a crafted HTTP request; configurable target, port, offset, and return address; attempt to trigger remote memory corruption and gain instruction-pointer control. Limitations: no real post-exploitation payload, no target fingerprinting, no reliability logic, no HTTPS/TLS handling, and no verification of successful exploitation beyond sending the request. Overall, this is best classified as a basic PoC exploit with placeholder shellcode and inconsistent targeting details.

bannned-bitDisclosed May 6, 2026pythonmarkdownnetworkweb
PAN-OS-User-ID-Buffer-Overflow-PoCMaturityPoCVerified exploit

This repository is a small standalone Python proof-of-concept for alleged CVE-2026-0300 affecting the Palo Alto Networks PAN-OS User-ID Authentication Portal. The repo contains only three files: an MIT LICENSE, a README describing the claimed vulnerability and usage, and a single executable script, research_poc.py. The script is the sole code artifact and clear entry point. The exploit logic is straightforward: it accepts a target IP, port, overflow offset, and return address from the command line; constructs a malicious buffer consisting of repeated 'A' padding, a user-supplied packed 64-bit return address, a short NOP sled, and INT3 bytes; then embeds that buffer directly as the body of an HTTP POST request to /php/login.php. It opens a raw TCP connection with socket.create_connection() to the specified host and port (default 6082), sends the request, and heuristically interprets the outcome based on whether the service closes the connection, responds, or times out. Main capabilities: network delivery of a crafted overflow request, configurable offset and return address for basic exploit experimentation, and simple response-based assessment of possible crash/vulnerable behavior. It does not contain a real shell payload, persistence, lateral movement, credential theft, or automated target discovery. The included payload bytes are placeholder/debug-oriented rather than a practical RCE implant. From a classification standpoint, this is an exploit PoC rather than merely a detector, because it actively sends a malformed request intended to corrupt memory. However, it remains relatively immature and research-oriented: there is no target fingerprinting, no architecture/version adaptation, no reliable exploitation chain, and no post-exploitation capability. The most realistic immediate effect of running it would be service instability or crash if the target were actually vulnerable.

qassam-315Disclosed May 6, 2026pythonmarkdownnetworkweb
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Palo Alto NetworksPan-Osapplication
PaloaltonetworksPan-Osoperating_system
SiemensRuggedcom Ape1808 Firmwareoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles against your asset inventory in the product.

ACTIVITY FEED

Recent activity

237 sources tracked across advisories, community write-ups, and news. Mallory keeps watching after this page renders.

237 SOURCESView all
The operational view lives in Mallory

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This page covers what’s public. Mallory adds the parts that aren’t — which of your assets are affected, which threat actors are using it right now, which detections to deploy, and what to do next.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence8

Every observed campaign linking this CVE to a named adversary.

Associated malware12

Malware families riding this exploit, with evidence and IOCs.

Detection signatures1

YARA, Sigma, Snort, and vendor rules — auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity181

Community discussion across Reddit, Mastodon, and other social sources.