Palo Alto Networks · PAN-OS
CVE-2022-0028
PAN-OS: Reflected Amplification Denial-of-Service (DoS) Vulnerability in URL Filtering
What it is
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.
CISA: A Palo Alto Networks PAN-OS URL filtering policy misconfiguration could allow a network-based attacker to conduct reflected and amplified TCP denial-of-service (RDoS) attacks.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: September 12, 2022
- Added to the CISA list
- August 22, 2022
- Published
- August 10, 2022
- Severity
- High 8.6 CVSS 3.1
- Chance of attacks in the next 30 days (EPSS)
- 2.7% in the top 14.2% of all known vulnerabilities
- Weakness
- CWE-940
- More details
- NVD · CVE.org · CISA
All references (1)
More exploited flaws from Palo Alto Networks
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Oct 14, 2026 | Code Injection | PAN-OS | High 8.6 | 1.7% |
| May 29, 2026 | Authentication Bypass | PAN-OS | High 7.8 | 95% |
| May 6, 2026 | Out-of-bounds Write | PAN-OS | Critical 9.3 | 42% |
| Feb 20, 2025 | File Read | PAN-OS | High 7.1 | 2.0% |
| Feb 18, 2025 | Authentication Bypass | PAN-OS | High 8.8 | 98% |
| Dec 30, 2024 | Malicious DNS Packet | PAN-OS | High 8.7 | 29% |
| Nov 18, 2024 | Management Interface Authentication Bypass | PAN-OS | Critical 9.3 | 99.8% |
| Nov 18, 2024 | Management Interface OS Command Injection | PAN-OS | Medium 6.9 | 94% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.