High severity · published Nov 10, 2021
CVE-2021-3063
An improper handling of exceptional conditions vulnerability exists in Palo Alto Networks GlobalProtect portal and gateway interfaces that enables an unauthenticated network-based…
7.5
CVSS
0.9%
EPSS
No
On KEV
Description
An improper handling of exceptional conditions vulnerability exists in Palo Alto Networks GlobalProtect portal and gateway interfaces that enables an unauthenticated network-based attacker to send specifically crafted traffic to a GlobalProtect interface that causes the service to stop responding. Repeated attempts to send this request result in denial of service to all PAN-OS services by restarting the device and putting it into maintenance mode. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.21; PAN-OS 9.0 versions earlier than PAN-OS 9.0.14-h4; PAN-OS 9.1 versions earlier than PAN-OS 9.1.11-h3; PAN-OS 10.0 versions earlier than PAN-OS 10.0.8-h4; PAN-OS 10.1 versions earlier than PAN-OS 10.1.3. Prisma Access customers are not impacted by this issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 61% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PA
PAN-OS · Palo Alto Networks
8.1.0 before 8.1.21; 9.0.0 through 9.0.14; 9.1.0 through 9.1.11; 10.0.0 through 10.0.8; 10.1.0 before 10.1.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3063
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3063
Vendor Advisory
https://security.paloaltonetworks.com/CVE-2021-3063
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