CVE-2020-2040 PAN-OS: Buffer overflow when Captive Portal or Multi-Factor Authentication (MFA) is enabled

What is CVE-2020-2040?

CVE-2020-2040 is a critical memory corruption vulnerability in Paloaltonetworks Pan-Os, published on 9 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-120

Which versions are affected by CVE-2020-2040?

It affects 1 product.

Products include Paloaltonetworks Pan-Os.

How do I fix CVE-2020-2040?

No fix has been published for CVE-2020-2040 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2020-2040 being exploited?

There is no known exploitation of CVE-2020-2040 in the wild and no public exploit code.

Other vulnerabilities in Paloaltonetworks Pan-Os

• CVE-2024-3400 Palo Alto Networks PAN-OS Command Injection Exploited Critical 10.0
• CVE-2020-2021 Palo Alto Networks PAN-OS Authentication Bypass Exploited Critical 10.0
• CVE-2017-15944 Palo Alto Networks PAN-OS Remote Code Execution Exploited Critical 9.8
• CVE-2026-0300 Palo Alto Networks PAN-OS Out-of-bounds Write Exploited Critical 9.3
• CVE-2024-0012 Palo Alto Networks PAN-OS Management Interface Authentication Bypass Exploited Critical 9.3

All Paloaltonetworks Pan-Os vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-pf79-9hv7-chg5.