PAN-OS: Denial-of-Service (DoS) Vulnerability in DNS Proxy

published 2022-04-13 4y ago modified 2026-06-17 4mo ago also EUVD-2022-15244

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

An improper handling of exceptional conditions vulnerability exists in the DNS proxy feature of Palo Alto Networks PAN-OS software that enables a meddler-in-the-middle (MITM) to send specifically crafted traffic to the firewall that causes the service to restart unexpectedly. Repeated attempts to send this request result in denial-of-service to all PAN-OS services by restarting the device in maintenance mode. This issue does not impact Panorama appliances and Prisma Access customers. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.22; PAN-OS 9.0 versions earlier than PAN-OS 9.0.16; PAN-OS 9.1 versions earlier than PAN-OS 9.1.13; PAN-OS 10.0 versions earlier than PAN-OS 10.0.10; PAN-OS 10.1 versions earlier than PAN-OS 10.1.5. This issue does not impact PAN-OS 10.2.

Patch / fix

fixed in 1

Palo Alto Networks PAN-OS 8.1.22, 9.0.16, 9.1.13, 10.0.10, 10.1.5

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Exploit prediction

0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:N/A:P

Affected products

Palo Alto Networks PAN-OS
Palo Alto Networks Prisma Access

Classification

Weakness

CWE-755 Improper Handling of Exceptional Conditions

Technology feeds

Palo Alto PAN-OS rss critical rss

References

security.paloaltonetworks.com /CVE-2022-0023
vendor-advisory

Sources

CVE List CVE-2022-0023
NVD CVE-2022-0023

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