CVE-2021-3055

PAN-OS: XML External Entity (XXE) Reference Vulnerability in the PAN-OS Web Interface

Description

An improper restriction of XML external entity (XXE) reference vulnerability in the Palo Alto Networks PAN-OS web interface enables an authenticated administrator to read any arbitrary file from the file system and send a specifically crafted request to the firewall that causes the service to crash. Repeated attempts to send this request result in denial of service to all PAN-OS services by restarting the device and putting it into maintenance mode. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.20; PAN-OS 9.0 versions earlier than PAN-OS 9.0.14; PAN-OS 9.1 versions earlier than PAN-OS 9.1.10; PAN-OS 10.0 versions earlier than PAN-OS 10.0.6. This issue does not affect Prisma Access.

Remediation

Solution:

  • This issue is fixed in PAN-OS 8.1.20, PAN-OS 9.0.14, PAN-OS 9.1.10, PAN-OS 10.0.6, and all later PAN-OS versions.

Workaround:

  • This issue requires the attacker to have authenticated access to the PAN-OS web interface. You can mitigate the impact of this issue by following best practices for securing the PAN-OS web interface. Please review the Best Practices for Securing Administrative Access in the PAN-OS technical documentation at https://docs.paloaltonetworks.com/best-practices.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Vendor Advisory paloaltonetworks.com
Affected: Palo Alto Networks PAN-OS
Published at:
Updated at:

References

Link Tags
https://security.paloaltonetworks.com/CVE-2021-3055 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3055?
CVE-2021-3055 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3055?
To fix CVE-2021-3055: This issue is fixed in PAN-OS 8.1.20, PAN-OS 9.0.14, PAN-OS 9.1.10, PAN-OS 10.0.6, and all later PAN-OS versions.
Is CVE-2021-3055 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3055 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-2021-3055?
CVE-2021-3055 affects Palo Alto Networks PAN-OS.
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