CVE-2021-22955 json
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 (Ga…
published 2021-12-07 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-10081
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 60%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- citrix gateway 11.1-65.23, 12.1-63.22, 13.0-83.27
- citrix application_delivery_controller_firmware 12.1-63.22, 13.0-83.27
Exploit prediction
0.92% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:N/A:P |
Affected products
- n/a Citrix ADC, Citrix Gateway
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
- Technology feeds
References
-
support.citrix.com
/article/CTX330728
vendor-advisory
Sources
- CVE List CVE-2021-22955
- NVD CVE-2021-22955
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