CVE-2026-0300Known exploitationNetwork attack vector

Unauthenticated root code execution via portal buffer overflow

Published May 6, 2026 · Updated May 6, 2026

Out-of-bounds write in PAN-OS 10.2, 11.1, 11.2, and 12.1 allows remote attackers to execute code as root via crafted portal packets. The User-ID Authentication Portal writes beyond a buffer boundary while handling crafted network traffic; Palo Alto Networks has not disclosed the affected function or field. Exposure requires the portal and Response Pages to be enabled on an L3 interface where untrusted traffic can ingress.

CVSS severity9.3
Critical
EPSS probability31.72%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in PAN-OS 10.2, 11.1, 11.2, and 12.1 allows remote attackers to execute code as root via crafted portal packets. The User-ID Authentication Portal writes beyond a buffer boundary while handling crafted network traffic; Palo Alto Networks has not disclosed the affected function or field. Exposure requires the portal and Response Pages to be enabled on an L3 interface where untrusted traffic can ingress.

The record

CVE
CVE-2026-0300
Published
May 6, 2026
Updated
May 6, 2026
Vendor
Palo Alto Networks
Product
PAN-OS
Classifications
CWE-787, CAPEC-100, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.2.0 <10.2.18-h6 changes=[{"at":"10.2.18-h6","status":"unaffected"},{"at":"10.2.16-h7","status":"unaffected"},{"at":"10.2.13-h21","status":"unaffected"},{"at":"10.2.10-h36","status":"unaffected"},{"at":"10.2.7-h34","status":"unaffected"}]
  2. Affected versionversion=11.1.0 <11.1.15 changes=[{"at":"11.1.15","status":"unaffected"},{"at":"11.1.13-h5","status":"unaffected"},{"at":"11.1.10-h25","status":"unaffected"},{"at":"11.1.7-h6","status":"unaffected"},{"at":"11.1.6-h32","status":"unaffected"},{"at":"11.1.4-h33","status":"unaffected"}]
  3. Affected versionversion=11.2.0 <11.2.12 changes=[{"at":"11.2.12","status":"unaffected"},{"at":"11.2.10-h6","status":"unaffected"},{"at":"11.2.7-h13","status":"unaffected"},{"at":"11.2.4-h17","status":"unaffected"}]
  4. Affected versionversion=12.1.0 <12.1.7 changes=[{"at":"12.1.7","status":"unaffected"},{"at":"12.1.4-h5","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Palo Alto Networks · PAN-OSversion=10.2.0 <10.2.18-h6 changes=[{"at":"10.2.18-h6","status":"unaffected"},{"at":"10.2.16-h7","status":"unaffected"},{"at":"10.2.13-h21","status":"unaffected"},{"at":"10.2.10-h36","status":"unaffected"},{"at":"10.2.7-h34","status":"unaffected"}]; version=11.1.0 <11.1.15 changes=[{"at":"11.1.15","status":"unaffected"},{"at":"11.1.13-h5","status":"unaffected"},{"at":"11.1.10-h25","status":"unaffected"},{"at":"11.1.7-h6","status":"unaffected"},{"at":"11.1.6-h32","status":"unaffected"},{"at":"11.1.4-h33","status":"unaffected"}]; version=11.2.0 <11.2.12 changes=[{"at":"11.2.12","status":"unaffected"},{"at":"11.2.10-h6","status":"unaffected"},{"at":"11.2.7-h13","status":"unaffected"},{"at":"11.2.4-h17","status":"unaffected"}]; version=12.1.0 <12.1.7 changes=[{"at":"12.1.7","status":"unaffected"},{"at":"12.1.4-h5","status":"unaffected"}]

Published CVSS scores

8.7Palo Alto NetworksCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N
9.3Palo Alto NetworksCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CAPEC-100Overflow Buffers
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Reported exploitation

Technologies

Your stack

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Your stack

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