CVE-2021-3047: Palo Alto Networks PAN-OS

Low severity, CVSS 3.1. EPSS: 0.5% chance of exploitation in the next 30 days.

A cryptographically weak pseudo-random number generator (PRNG) is used during authentication to the Palo Alto Networks PAN-OS web interface. This enables an authenticated attacker, with the capability to observe their own authentication secrets over a long duration on the PAN-OS appliance, to impersonate another authenticated web interface administrator's session. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.19; 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 10.0.4. PAN-OS 10.1 versions are not impacted.

Affected products

• Palo Alto Networks PAN-OS: from 8.1.0, before 8.1.19 (fixed in 8.1.19); from 9.0.0, before 9.0.14 (fixed in 9.0.14); from 9.1.0, before 9.1.10 (fixed in 9.1.10); from 10.0.0, before 10.0.4 (fixed in 10.0.4)

Published 2021-08-11. Last modified 2026-06-17.