Pan OsOperating system · Paloaltonetworks
CVE-2022-0028
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA PAN-OS URL filtering policy misconfiguration could allow a network-based attacker to conduct reflected and amplified TCP denial-of-service (RDoS) attacks. The DoS attack would appear to originate from a Palo Alto Networks PA-Series (hardware), VM-Series (virtual) and CN-Series (container) firewall against an attacker-specified target. To be misused by an external attacker, the firewall configuration must have a URL filtering profile with one or more blocked categories assigned to a source zone that has an external facing interface. This configuration is not typical for URL filtering and, if set, is likely unintended by the administrator. If exploited, this issue would not impact the confidentiality, integrity, or availability of our products. However, the resulting denial-of-service (DoS) attack may help obfuscate the identity of the attacker and implicate the firewall as the source of the attack. We have taken prompt action to address this issue in our PAN-OS software. All software updates for this issue are expected to be released no later than the week of August 15, 2022. This issue does not impact Panorama M-Series or Panorama virtual appliances. This issue has been resolved for all Cloud NGFW and Prisma Access customers and no additional action is required from them.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidencePAN-OS URL filtering policy misconfiguration allows external attackers to abuse firewalls (PA-Series, VM-Series, CN-Series) as reflectors/amplifiers in reflected TCP DoS attacks. Attack requires URL filtering profile with blocked categories assigned to a source zone containing external-facing interfaces - this configuration is atypical and unintended.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Pan OsOperating system
>= 8.1.0, < 8.1.23>= 9.0.0, < 9.0.16>= 9.1.0, < 9.1.14>= 10.0.0, < 10.0.11>= 10.1.0, < 10.1.6>= 10.2.0, < 10.2.2= 8.1.23= 9.0.16= 9.1.14= 10.0.11= 10.1.6= 10.2.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Verify PAN-OS versionRun 'show system info' or check the dashboard to confirm the installed PAN-OS versionAffected if The installed version falls within these ranges: 8.1.0-8.1.23, 9.0.0-9.0.16, 9.1.0-9.1.14, 10.0.0-10.0.11, 10.1.0-10.1.6, or 10.2.0-10.2.2 (excluding the fixed versions 8.1.24+, 9.0.17+, 9.1.15+, 10.0.12+, 10.1.7+, 10.2.3+)
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Identify external-facing interfaces and their zonesNavigate to Network > Interfaces and review each interface's zone assignment. Identify interfaces with Zone type set to 'Layer3' and that connect to untrusted/external networksAffected if Any interface connected to external networks is assigned to a zone
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Review URL filtering profiles for blocked categoriesGo to Objects > URL Filtering and examine each profile. Check if any category is set to 'Block' or 'block' actionAffected if A URL filtering profile exists with at least one category set to Block
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Check security policy rules binding URL filtering to zonesGo to Policies > Security and review each rule. Identify rules that reference a URL filtering profile and note the Source Zone specifiedAffected if A security rule applies a URL filtering profile with blocked categories to traffic originating from a zone that contains external-facing interfaces
You are affected if running an affected PAN-OS version AND a URL filtering profile with blocked categories is bound to a security rule with a source zone that includes external-facing interfaces, creating an unintended reflector configuration for DDoS amplification.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped8.1.239.0.169.1.14
Review URL filtering profiles assigned to zones with external-facing interfaces and remove any blocked category configurations from such zones; apply vendor patches when released. This misconfiguration should not exist in production environments.
PAN-OS 8.1.23+ (8.1.x), 9.0.16+ (9.0.x), 9.1.14+ (9.1.x), or 10.0.11+ (10.0.x)
- 1. Identify the current PAN-OS version on PA-Series (hardware), VM-Series (virtual), or CN-Series (container) firewalls
- 2. Plan upgrade to the fixed version based on current branch: PAN-OS 8.1.23 or later (for 8.1.x branch), PAN-OS 9.0.16 or later (for 9.0.x branch), PAN-OS 9.1.14 or later (for 9.1.x branch), or PAN-OS 10.0.11 or later (for 10.0.x branch)
- 3. Before upgrading, verify URL filtering profile configuration to ensure blocked categories are NOT assigned to source zones with external-facing interfaces
- 4. Perform upgrade following standard Palo Alto Networks upgrade procedures
- 5. After upgrade, verify the configuration no longer contains the vulnerable URL filtering setup
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Pan Os
Exploited in the wild — priority engagement
- Consultation4.0 h
- Implementation3.0 h
- Testing5.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,208.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-0028 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-0028 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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