CVE-2026-3055
Insufficient input validation leading to memory overread
Citrix NetScaler Out-of-Bounds Read Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA notes
https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696300&articleURL=NetScaler_ADC_and_NetScaler_Gateway_Security_Bulletin_for_CVE_2026_3055_and_CVE_2026_4368 ; https://nvd.nist.gov/vuln/detail/CVE-2026-3055
Description
Insufficient input validation in NetScaler ADC and NetScaler Gateway when configured as a SAML IDP leading to memory overread
Severity
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:LExploitation Context
as of October 15, 2026- CISA added CVE-2026-3055 to the KEV catalog 7 days after its CVE record was published. The median for entries added in 2026 so far is 14 days.
- It is one of 27 Citrix entries in the CISA KEV catalog, and one of 6 added in 2026.
- Its current EPSS score (4.0%) is higher than that of 16% of CISA KEV entries.
Affected Products
| Vendor | Product | Affected versions |
|---|---|---|
| NetScaler | NetScaler ADC | 14.1 to <66.59 13.1 to <62.23 13.1 FIPS and NDcPP to <37.262 |
| NetScaler | NetScaler Gateway | 14.1 to <66.59 13.1 to <62.23 |
References
1 LinksRecord Details
More from Citrix
NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-19490
Memory overflow vulnerability leading to Remote Code Execution and/or Denial of Service
Memory overflow vulnerability leading to Remote Code Execution or Denial of Service
A remote code execution vulnerability exists due to improper input validation, which can allow an unauthenticated attacker to execute arbitrary commands
Related
Tool categories
CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.