Signal

Critical unauthenticated buffer overflow vulnerability exploited in Palo Alto Networks PAN-OS firewalls

Evidence first: scan the strongest sources, then decide whether to go deeper.

Published 2026-05-06 00:11 UTCUpdated 2026-05-06 13:31 UTC
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Evidence trail (top sources)
top sources (4 domains)domains are deduped. counts indicate coverage, not truth.
4 top sources shown
Palo Alto Networks security advisory (AV26-425)
Canadian Centre for Cyber Security - Alerts · News · cyber.gc.ca · 2026-05-06 13:31 UTC
2026-006: Critical Vulnerability in PAN-OS
CERT-EU Security Advisories · cert.europa.eu · 2026-05-06 08:48 UTC
Overview

A critical buffer overflow vulnerability (CVE-2026-0300) affecting the User-ID Authentication Portal in Palo Alto Networks PAN-OS software is being actively exploited in the wild.

Entities
Palo Alto NetworksPAN-OSUser-ID Authentication Portal
Score total
1.98
Momentum 24h
7
Posts
7
Origins
7
Source types
1
Duplicate ratio
0%
Why now
  • Exploitation has been confirmed in the wild, targeting exposed Authentication Portals.
  • Patches are not yet available but expected starting May 13, 2026, requiring interim mitigations.
  • The vulnerability affects multiple PAN-OS versions and firewall models, broadening the impact scope.
Why it matters
  • The vulnerability allows unauthenticated remote attackers to execute code with root privileges, risking full firewall compromise.
  • Palo Alto Networks firewalls are widely deployed in enterprise networks, making this a significant security risk.
  • Active exploitation in the wild increases urgency for patching and mitigation to prevent breaches.
LLM analysis
Topic mix: lowPromo risk: lowSource quality: high
Recurring claims
  • CVE-2026-0300 is a critical unauthenticated buffer overflow vulnerability in Palo Alto PAN-OS User-ID Authentication Portal allowing remote root code execution.
How sources frame it
  • Rapid7: neutral
  • Canadian Centre For Cyber Security: neutral
  • CERT-EU: neutral
All evidence
All evidence
Palo Alto Networks security advisory (AV26-425)
Canadian Centre for Cyber Security - Alerts · cyber.gc.ca · 2026-05-06 13:31 UTC
Root-level RCE vulnerability in Palo Alto firewalls exploited (CVE-2026-0300)
Help Net Security · helpnetsecurity.com · 2026-05-06 09:51 UTC
2026-006: Critical Vulnerability in PAN-OS
CERT-EU Security Advisories · cert.europa.eu · 2026-05-06 08:48 UTC
Palo Alto PAN-OS Flaw Under Active Exploitation Enables Remote Code Execution
thehackernews · thehackernews.com · 2026-05-06 06:14 UTC
Palo Alto Networks to Patch Zero-Day Exploited to Hack Firewalls
SecurityWeek · securityweek.com · 2026-05-06 04:46 UTC
Show filters & breakdown
Posts loaded: 0Publishers: 6Origin domains: 6Duplicates: -
Showing 6 / 0
Top publishers (this list)
  • Canadian Centre for Cyber Security - Alerts (1)
  • Rapid7 Blog (1)
  • Help Net Security (1)
  • CERT-EU Security Advisories (1)
  • thehackernews (1)
  • SecurityWeek (1)
Top origin domains (this list)
  • cyber.gc.ca (1)
  • rapid7.com (1)
  • helpnetsecurity.com (1)
  • cert.europa.eu (1)
  • thehackernews.com (1)
  • securityweek.com (1)