Home/CVE/A unauthenticated denial of service vulnerability exists in Citrix ADC <13.0-83.27, <12.1-63.22 and 11.1-65.23 when conf
CVE

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 conf

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.

HIGH · CVSS 7.5 EPSS 0.00508
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-400Uncontrolled Resource Consumption
CWE-400Uncontrolled Resource Consumption
▤

Affected Products & Versions

6
citrix application delivery controller firmware<= 11.1-65.23
citrix application delivery controller firmware>= 12.1 and < 12.1-63.22
citrix application delivery controller firmware>= 13.0 and < 13.0-83.27
citrix gateway< 11.1-65.23
citrix gateway>= 12.1 and < 12.1-63.22
citrix gateway>= 13.0 and < 13.0-83.27
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumAzure Application Gateway Modified or Deleted
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · support@hackerone.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD07 Dec 2021 · 02:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://support.citrix.com/article/CTX330728Vendor Advisory
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