CVE-2020-2040

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

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.

Remediation

Solution:

  • This issue is fixed in PAN-OS 8.1.15, PAN-OS 9.0.9, PAN-OS 9.1.3, and all later PAN-OS versions. All Prisma Access services are now upgraded to resolve this issue and are no longer vulnerable. PAN-OS 7.1 and 8.0 are end-of-life and are no longer covered by our Product Security Assurance policies.

Workaround:

  • Until PAN-OS software is upgraded to a fixed version, enabling signatures in content update version 8317 will block attacks against CVE-2020-2040.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 3.99% Top 15%
Vendor Advisory paloaltonetworks.com
Affected: Palo Alto Networks PAN-OS
Published at:
Updated at:

References

Link Tags
https://security.paloaltonetworks.com/CVE-2020-2040 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-2040?
CVE-2020-2040 has been scored as a critical severity vulnerability.
How to fix CVE-2020-2040?
To fix CVE-2020-2040: This issue is fixed in PAN-OS 8.1.15, PAN-OS 9.0.9, PAN-OS 9.1.3, and all later PAN-OS versions. All Prisma Access services are now upgraded to resolve this issue and are no longer vulnerable. PAN-OS 7.1 and 8.0 are end-of-life and are no longer covered by our Product Security Assurance policies.
Is CVE-2020-2040 being actively exploited in the wild?
It is possible that CVE-2020-2040 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~4% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-2040?
CVE-2020-2040 affects Palo Alto Networks PAN-OS.
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