CVE-2021-3031

PAN-OS: Information exposure in Ethernet data frame construction (Etherleak)

Description

Padding bytes in Ethernet packets on PA-200, PA-220, PA-500, PA-800, PA-2000 Series, PA-3000 Series, PA-3200 Series, PA-5200 Series, and PA-7000 Series firewalls are not cleared before the data frame is created. This leaks a small amount of random information from the firewall memory into the Ethernet packets. An attacker on the same Ethernet subnet as the PAN-OS firewall is able to collect potentially sensitive information from these packets. This issue is also known as Etherleak and is detected by security scanners as CVE-2003-0001. This issue impacts: PAN-OS 8.1 version earlier than PAN-OS 8.1.18; PAN-OS 9.0 versions earlier than PAN-OS 9.0.12; PAN-OS 9.1 versions earlier than PAN-OS 9.1.5.

Remediation

Solution:

  • This issue is fixed in PAN-OS 8.1.18, PAN-OS 9.0.12, PAN-OS 9.1.5, and all later PAN-OS versions.

Workaround:

  • There is no workaround to prevent the information leak in the Ethernet packets; however, restricting access to the networks mitigates the risk of this issue.

Categories

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Vendor Advisory paloaltonetworks.com
Affected: Palo Alto Networks PAN-OS
Affected: Palo Alto Networks PAN-OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-3031?
CVE-2021-3031 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3031?
To fix CVE-2021-3031: This issue is fixed in PAN-OS 8.1.18, PAN-OS 9.0.12, PAN-OS 9.1.5, and all later PAN-OS versions.
Is CVE-2021-3031 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3031 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3031?
CVE-2021-3031 affects Palo Alto Networks PAN-OS, Palo Alto Networks PAN-OS.
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