CVE-2021-3048

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

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.

Remediation

Solution:

  • This issue is fixed in PAN-OS 9.0.14, PAN-OS 9.1.9, PAN-OS 10.0.5, and all later PAN-OS versions. If a firewall encounters this problem, you will require TAC assistance to make the firewall operational again.

Workaround:

  • You can prevent this issue by removing all invalid URL entries from source EDLs or removing the EDL from your configuration. Additionally, do not configure EDLs from websites that you do not trust.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.78% Top 30%
Vendor Advisory paloaltonetworks.com
Affected: Palo Alto Networks PAN-OS
Published at:
Updated at:

References

Link Tags
https://security.paloaltonetworks.com/CVE-2020-3048 broken link
https://security.paloaltonetworks.com/CVE-2021-3048 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3048?
CVE-2021-3048 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3048?
To fix CVE-2021-3048: This issue is fixed in PAN-OS 9.0.14, PAN-OS 9.1.9, PAN-OS 10.0.5, and all later PAN-OS versions. If a firewall encounters this problem, you will require TAC assistance to make the firewall operational again.
Is CVE-2021-3048 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3048 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3048?
CVE-2021-3048 affects Palo Alto Networks PAN-OS.
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