Actively exploited · Published Sep 27, 2026 · Assigned by NetScaler
CVE-2026-88772Memory overflow vulnerability leading to Remote Code Execution or Denial of Service
Critical 9.5 Exploited
In plain English
A critical-severity memory corruption in ADC from Citrix NetScaler. Attackers are actively exploiting it in the wild (listed by CISA on September 27, 2026). The chance it is exploited in the next 30 days is estimated at 76.6% (higher than 99.5% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit, public proof-of-concept code. 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.
CISA guidance
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.
Federal agencies must remediate by Sep 30, 2026.
Official description
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 Remote Code Execution or Denial of Service
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Citrix NetScaler | ADC | 0 – before 14.1-73.370 – before 13.1-64.230 – before 14.1-73.37 FIPS0 – before 13.1.37.279 FIPS and NDcPP |
| Citrix NetScaler | Gateway | 0 – before 14.1-73.370 – before 13.1-64.23 |
Weakness: CWE-119 · Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
References
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096&articleTitle=Citrix_NetScaler_ADC_and_Citrix_NetScaler_Gateway_Security_Bulletin_for_CVE_2026_88771_CVE_2026_88772_CVE_2026_88773_CVE_2026_88774_CVE_2026_88775_CVE_2026_88776_CVE_2026_88777_and_CVE_2026_88778
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-88772 government-resource