High severity · published Dec 7, 2021
CVE-2021-22955
A unauthenticated denial of service vulnerability exists in Citrix ADC <13.0-83.27, <12.1-63.22 and 11.1-65.23 when configured as a VPN (Gateway) or AAA virtual server could allow…
7.5
CVSS
0.9%
EPSS
No
On KEV
Description
A unauthenticated denial of service vulnerability exists in Citrix ADC <13.0-83.27, <12.1-63.22 and 11.1-65.23 when configured as a VPN (Gateway) or AAA virtual server could allow an attacker to cause a temporary disruption of the Management GUI, Nitro API, and RPC communication.
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 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NA
NetScaler ADC · Citrix
before 11.1-65.23; 12.1 before 12.1-63.22; 13.0 before 13.0-83.27 · source: NVD
AD
Application Delivery Controller Firmware · Citrix
through 11.1-65.23; 12.1 before 12.1-63.22; 13.0 before 13.0-83.27 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22955
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22955
Vendor Advisory
https://support.citrix.com/article/CTX330728
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