CVE-2021-3055: PAN-OS: XML External Entity (XXE) Reference Vulnerability in the PAN-OS Web Interface

Published Sep 8, 2021
·
Updated

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.

Affected Software

4 affected components
Palo Alto Networks PAN-OS>=8.1.0<8.1.20
Palo Alto Networks PAN-OS>=9.0.0<9.0.14
Palo Alto Networks PAN-OS>=9.1.0<9.1.10
Palo Alto Networks PAN-OS>=10.0.0<10.0.6

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Palo Alto Networks PAN-OS to a version that resolves this vulnerability.

    Fixed in 8.1.20
  2. Upgrade

    Upgrade Palo Alto Networks PAN-OS to a version that resolves this vulnerability.

    Fixed in 9.0.14
  3. Upgrade

    Upgrade Palo Alto Networks PAN-OS to a version that resolves this vulnerability.

    Fixed in 9.1.10
  4. Upgrade

    Upgrade Palo Alto Networks PAN-OS to a version that resolves this vulnerability.

    Fixed in 10.0.6

Event History

Sep 8, 2021
CVE Published
via MITRE·05:10 PM
Data Sourced
via MITRE·05:10 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·05:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2021-3055?

CVE-2021-3055 is an improper restriction of XML external entity (XXE) reference vulnerability in the Palo Alto Networks PAN-OS web interface.

2

How does CVE-2021-3055 impact Palo Alto Networks PAN-OS?

CVE-2021-3055 allows an authenticated administrator to read any arbitrary file from the file system and crash the service by sending a specifically crafted request to the firewall.

3

Which versions of Palo Alto Networks PAN-OS are affected by CVE-2021-3055?

Palo Alto Networks PAN-OS versions 8.1.0 to 8.1.20, 9.0.0 to 9.0.14, 9.1.0 to 9.1.10, and 10.0.0 to 10.0.6 are affected by CVE-2021-3055.

4

What is the severity of CVE-2021-3055?

CVE-2021-3055 has a severity rating of 6.5, which is considered high.

5

How can the CVE-2021-3055 vulnerability be fixed?

To fix the CVE-2021-3055 vulnerability, Palo Alto Networks users should upgrade to a version that is not affected by the vulnerability. Please refer to the official Palo Alto Networks security advisory for specific version details.

Contact

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