CVE-2026-88771 (GCVE-0-2026-88771)
Vulnerability from cvelistv5
Published
2026-09-27 16:02
Modified
2026-09-29 03:55
Severity ?
9.5 (Critical) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CWE
  • CWE-20 - Improper input validation
Summary
Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to an unauthenticated attacker to execute arbitrary commands.
References
Impacted products
Vendor Product Version
Citrix NetScaler ADC Version: 0
Version: 0
Version: 0
Version: 0
 Create a notification for this product.
CISA Known Exploited Vulnerability
Data from the CISA Known Exploited Vulnerabilities Catalog

Date added: 2026-09-27

Due date: 2026-09-30

Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Used in ransomware: Unknown

Notes: Running the provided IOCs in the NetScaler console may help identify indicators of exploitation. Customers must conduct forensic triage as directed by BOD 26‑04 and follow Citrix’s published guidance for mitigations. For more information, please see: https://community.citrix.com/techzone-blogs/110_security-updates/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve-2026-88771-through-cve-2026-88778 ; https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096 ; https://support.citrix.com/external/article/CTX694799/steps-to-take-if-netscaler-adc-is-suspec.html ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-88772

Show details on NVD website

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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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