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CVE-2021-3055

MEDIUM severity · CVSS 6.5 · XML external entity (XXE)
6.5CVSS MEDIUM

Summary

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.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredHigh
User interactionNone
Confidentiality impactHigh
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)1%

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.