CVE-2020-2040

PAN-OS: Buffer overflow when Captive Portal or Multi-Factor Authentication (MFA) is enabled

CRITICAL
9.8
CVSS Score
Published: September 9, 2020 at 04:45 PM UTC
Updated: June 17, 2026 at 03:11 AM UTC
1 product affected across 1 vendorPAN-OS

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Severity
CRITICAL9.8
Exploit prediction
EPSS 4%

Description

A buffer overflow vulnerability in PAN-OS allows an unauthenticated attacker to disrupt system processes and potentially execute arbitrary code with root privileges by sending a malicious request to the Captive Portal or Multi-Factor Authentication interface. This issue impacts: All versions of PAN-OS 8.0; PAN-OS 8.1 versions earlier than PAN-OS 8.1.15; PAN-OS 9.0 versions earlier than PAN-OS 9.0.9; PAN-OS 9.1 versions earlier than PAN-OS 9.1.3.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

8.0.0 ≤ v ≤ 8.0.208.1 ≤ v < 8.1.158.1.0 ≤ v < 8.1.159.0 ≤ v < 9.0.99.0.0 ≤ v < 9.0.99.1 ≤ v < 9.1.39.1.0 ≤ v < 9.1.38.0.*8.19.09.1
Vendor states this is fixed in 10.0.0 (unaffected)
Affected range stops below 8.1.15, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.0.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.1.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

CVSS

9.8CRITICALpalo_alto
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-120

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