Palo Alto Networks PAN-OS Reflected Amplification Denial-of-Service
CVE-2022-0028 is a high-severity insufficient control of network message volume (network amplification) vulnerability in Cloud NGFW from Palo Alto Networks, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. CISA added it to the Known Exploited Vulnerabilities catalogue on August 22, 2022, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update PAN-OS to 8.1.23-h1 or 9.0.16-h3 or 9.1.14-h4 or 10.0.11-h1, whichever matches your release line, or a later version.
- CISA's required action: Apply updates per vendor instructions.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Palo Alto Networks | Cloud NGFW | Not specified in the record | Not stated |
| Palo Alto Networks | PAN-OS | 8.1 up to, but not including, 8.1.23-h1; 9.0 up to, but not including, 9.0.16-h3; 9.1 up to, but not including, 9.1.14-h4; 10.0 up to, but not including, 10.0.11-h1; 10.1 up to, but not including, 10.1.6-h6; 10.2 up to, but not including, 10.2.2-h2; 8.1.0 up to, but not including, 8.1.23-h; 9.0.0 up to, but not including, 9.0.16-h3; and 4 more ranges | 8.1.23-h1, 9.0.16-h3, 9.1.14-h4, 10.0.11-h1, 10.1.6-h6, 10.2.2-h2 |
| Palo Alto Networks | Prisma Access | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.6 | High | CNA (paloaltonetworks.com) |
| CVSS 3.1 | 8.6 | High | NVD |
Official description
A 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insufficient Control of Network Message Volume (Network Amplification)
The product does not sufficiently monitor or control transmitted network traffic volume, so that an actor can cause the product to transmit more traffic than should be allowed for that actor.
How developers prevent this class of flaw
- An application must make network resources available to a client commensurate with the client's access level.
- Define a clear policy for network resource allocation and consumption.
- An application must, at all times, keep track of network resources and meter their usage appropriately.
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- security.paloaltonetworks.com/CVE-2022-0028Mitigation, Third Party Advisory
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-0028US Government Resource
Other vulnerabilities in Cloud NGFW
- 7.2 High severity
Palo Alto Networks PAN-OS Code Injection Exploited
- 7.2 High severity
- 7.5 High severity
- 7.5 High severity
- 7.2 High severity
- 9.9 Critical severity
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