CVE-2022-0028Known exploitationNetwork attack vector

Third-party service interruption via reflected TCP amplification

Published Aug 10, 2022 · Updated Oct 21, 2025

URL filtering in Palo Alto Networks PAN-OS allows remote attackers to amplify reflected TCP denial-of-service traffic toward other systems. When a blocked URL category is assigned to a security rule whose source zone has an external-facing interface, crafted TCP requests elicit amplified responses with the firewall address as the apparent source. This atypical configuration exposes the behavior without authentication; the traffic can interrupt an attacker-selected target and implicate the firewall, but does not compromise the firewall itself.

CVSS severity8.6
High
EPSS probability2.38%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

URL filtering in Palo Alto Networks PAN-OS allows remote attackers to amplify reflected TCP denial-of-service traffic toward other systems. When a blocked URL category is assigned to a security rule whose source zone has an external-facing interface, crafted TCP requests elicit amplified responses with the firewall address as the apparent source. This atypical configuration exposes the behavior without authentication; the traffic can interrupt an attacker-selected target and implicate the firewall, but does not compromise the firewall itself.

The record

CVE
CVE-2022-0028
Published
Aug 10, 2022
Updated
Oct 21, 2025
Vendor
Palo Alto Networks
Product
PAN-OS
Classifications
CWE-406, T1498.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 10, 2022CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.0 <10.0.11-h1
  2. Affected versionversion=10.0 <10.0.11-h1 changes=[{"at":"10.0.11-h1","status":"unaffected"}]
  3. Affected versionversion=10.1.0 <10.1.6-h6
  4. Affected versionversion=10.1 <10.1.6-h6 changes=[{"at":"10.1.6-h6","status":"unaffected"}]
  5. Affected versionversion=10.2.0 <10.2.2-h2
  6. Affected versionversion=10.2 <10.2.2-h2 changes=[{"at":"10.2.2-h2","status":"unaffected"}]
  7. Affected versionversion=8.1.0 <8.1.23-h
  8. Affected versionversion=8.1 <8.1.23-h1 changes=[{"at":"8.1.23-h1","status":"unaffected"}]
  9. Affected versionversion=9.0.0 <9.0.16-h3
  10. Affected versionversion=9.0 <9.0.16-h3 changes=[{"at":"9.0.16-h3","status":"unaffected"}]
  11. Affected versionversion=9.1.0 <9.1 < 9.1.14-h4
  12. Affected versionversion=9.1 <9.1.14-h4 changes=[{"at":"9.1.14-h4","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Palo Alto Networks · PAN-OSversion=10.0.0 <10.0.11-h1; version=10.0 <10.0.11-h1 changes=[{"at":"10.0.11-h1","status":"unaffected"}]; version=10.1.0 <10.1.6-h6; version=10.1 <10.1.6-h6 changes=[{"at":"10.1.6-h6","status":"unaffected"}]; version=10.2.0 <10.2.2-h2; version=10.2 <10.2.2-h2 changes=[{"at":"10.2.2-h2","status":"unaffected"}]; version=8.1.0 <8.1.23-h; version=8.1 <8.1.23-h1 changes=[{"at":"8.1.23-h1","status":"unaffected"}]; version=9.0.0 <9.0.16-h3; version=9.0 <9.0.16-h3 changes=[{"at":"9.0.16-h3","status":"unaffected"}]; version=9.1.0 <9.1 < 9.1.14-h4; version=9.1 <9.1.14-h4 changes=[{"at":"9.1.14-h4","status":"unaffected"}]

Published CVSS scores

8.6Palo Alto NetworksCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-406Insufficient Control of Network Message Volume (Network Amplification)
T1498.002Network Denial of Service: Reflection Amplification

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo