What is CVE-2022-0028?

CVE-2022-0028 is PAN-OS: Reflected Amplification Denial-of-Service (DoS) Vulnerability in URL Filtering. The supplied enrichment data classifies it as Denial of Service mapped to CWE-406 CWE-406.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Yes: CISA KEV signal present. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

Yes. The supplied enrichment data lists CVE-2022-0028 in CISA KEV with required action: Apply updates per vendor instructions.. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

15 public PoC repositories reported; 3 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2022-0028 using CVSS 8.6, EPSS 2%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

Workarounds are not confirmed from current sources. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Treat as emergency remediation because CISA KEV status is present. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

CISA KEVhighDenial of Servicepublic exploit

CVE-2022-0028

CVE-2022-0028 — PAN-OS: Reflected Amplification Denial-of-Service (DoS) Vulnerability in URL Filtering

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.

Published Aug 10, 2022Updated Jun 17, 2026Sources: NVD, Palo Alto Networks (CNA), CISA, FIRST EPSS, GitHub

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Confirmed

CISA KEV, listed Aug 22, 2022

EPSS

ahead of 83% of scored CVEs

Affects

Palo Alto

11 products listed

CVSS base

8.6

high

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

Active

none · proof-of-concept · active

Automatable

Yes

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

We identified workarounds to prevent the denial-of-service (DoS) attacks that result from this issue in certain Palo Alto Networks firewalls, with this policy configuration We intend to fix this issue for PA-Series, VM-Series and CN-Series firewalls with a fix in the following PAN-OS software releases: PAN-OS 8.1.23-h1 (ETA: week of August 8, 2022), PAN-OS 9.0.16-h3 (ETA: week of August 15, 2022), PAN-OS 9.1.14-h4 (ETA: week of August 15, 2022), PAN-OS 10.0.11-h1 (ETA: week of August 15, 2022), PAN-OS 10.1.6-h6 (ETA: week of August 8, 2022), and PAN-OS 10.2.2-h2 (ETA: week of August 15, 2022)…

CISA required action

Apply updates per vendor instructions.

Federal deadline Sep 12, 2022 — passed 1,475 days ago

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Treat as emergency remediation because CISA KEV status is present.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
Palo Alto	Cloud NGFW	All	Patched
Palo Alto	PAN-OS	8.1 to < 8.1.23-h1	Vulnerable
Palo Alto	PAN-OS	9.0 to < 9.0.16-h3	Vulnerable
Palo Alto	PAN-OS	9.1 to < 9.1.14-h4	Vulnerable
Palo Alto	PAN-OS	10.0 to < 10.0.11-h1	Vulnerable
Palo Alto	PAN-OS	10.1 to < 10.1.6-h6	Vulnerable
Palo Alto	PAN-OS	10.2 to < 10.2.2-h2	Vulnerable
Palo Alto	Prisma Access	2.1 All	Patched
Palo Alto	Prisma Access	2.2 All	Patched
Palo Alto	Prisma Access	3.0 All	Patched
Palo Alto	Prisma Access	3.1 All	Patched

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

High

Confidentiality

None

Integrity

None

Scope

Changed

Attack Complexity

Low

Attack Vector

Network

Privileges Req

None

User Interaction

None

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
8.6	CVSS 3.1	high	3.9	4	Palo Alto Networks (CNA), NVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Weakness & attack patterns

CWE-406

Inferred from the weakness class — not observed against this CVE.

CAPEC-125 · FloodingCAPEC-130 · Excessive Allocation

CISA KEV details

CISA lists a CVE here once it has evidence of exploitation against real targets.

CISAThat month →

Listed

Aug 22, 2022

Federal deadline

Sep 12, 2022

passed 1,475 days ago

Ransomware use

Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a date to argue against.

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

3 of the 5 sampled are weaponized

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Prioritize edge telemetry for network-reachable Cloud NGFW, PAN-OS, Prisma Access.
Monitor for scanner or exploit-pattern traffic after 15 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 8.6 (AV:N)
Jun 17, 2026 · NVD
2022
Added to CISA KEV catalog
Aug 22, 2022 · CISA
Initial · CVE published
Aug 10, 2022 · NVD
Reported · Initial publication
Aug 10, 2022 · Palo Alto Networks

References

3 on the record

security.paloaltonetworks.com/CVE-2022-0028
Mitigation, Third Party Advisory, Vendor Advisory
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-0028
US Government Resource
nvd.nist.gov/vuln/detail/CVE-2022-0028
Vendor Advisory

Elsewhere on this site

Palo Altoevery CVE for this vendor
August 2022what else CISA listed
Denial of Servicesame class
CWE-406other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2022-0028 is PAN-OS: Reflected Amplification Denial-of-Service (DoS) Vulnerability in URL Filtering, a high vulnerability affecting Cloud NGFW, PAN-OS, Prisma Access from Palo Alto Networks. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 15 public PoC repositories reported; 3 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.6 describes technical severity, while EPSS 2% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.