CVE-2020-2031: PAN-OS: Integer underflow in the management interface

Severity: medium (CVSS 4.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-07-08 · updated 2026-06-17
Weakness: CWE-191

Description

An integer underflow vulnerability in the dnsproxyd component of the PAN-OS management interface allows authenticated administrators to issue a command from the command line interface that causes the component to stop responding. 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 9.1 versions earlier than PAN-OS 9.1.3. This issue does not impact PAN-OS 8.1, PAN-OS 9.0, or Prisma Access services.

Affected products

Palo Alto Networks PAN-OS: from 9.1.0 before 9.1.3 — fixed in 9.1.3
Palo Alto Networks PAN-OS: from 9.1 before 9.1.3 — fixed in 9.1.3

How to fix

Upgrade to a fixed version: Palo Alto Networks PAN-OS 9.1.3; Palo Alto Networks PAN-OS 9.1.3. Check the vendor advisory for mitigations.

References

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