CVE-2021-3048: PAN-OS: Invalid URLs in an External Dynamic List (EDL) can Lead to Firewall Outage

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-08-11 · updated 2026-06-17
Weakness: CWE-20

Description

Certain invalid URL entries contained in an External Dynamic List (EDL) cause the Device Server daemon (devsrvr) to stop responding. This condition causes subsequent commits on the firewall to fail and prevents administrators from performing commits and configuration changes even though the firewall remains otherwise functional. If the firewall then restarts, it results in a denial-of-service (DoS) condition and the firewall stops processing traffic. This issue impacts: PAN-OS 9.0 versions earlier than PAN-OS 9.0.14; PAN-OS 9.1 versions earlier than PAN-OS 9.1.9; PAN-OS 10.0 versions earlier than PAN-OS 10.0.5. PAN-OS 8.1 and PAN-OS 10.1 versions are not impacted.

Affected products

Palo Alto Networks PAN-OS: from 9.0.0 before 9.0.14; from 9.1.0 before 9.1.9; from 10.0.0 before 10.0.5 — fixed in 9.0.14, 9.1.9, 10.0.5
Palo Alto Networks PAN-OS: from 9.0 before 9.0.14; from 9.1 before 9.1.9; from 10.0 before 10.0.5 — fixed in 9.0.14, 9.1.9, 10.0.5

How to fix

Upgrade to a fixed version: Palo Alto Networks PAN-OS 9.0.14, 9.1.9, 10.0.5; Palo Alto Networks PAN-OS 9.0.14, 9.1.9, 10.0.5. Check the vendor advisory for mitigations.

References

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