CVE-2026-88779
Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 7 October 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
Vulnerability in NetScaler ADC and NetScaler Gateway. This issue affects ADC: before 14.1-73.41, before 13.1-64.28, before 14.1-73.41 FIPS, and before 13.1-37.282; Gateway: before 14.1-73.41 and before 13.1-64.28.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.59% probability · 48th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 4 October 2026 · due 7 October 2026
- Weakness
- CWE-119
- Affected
- citrix/netscaler application delivery controller · citrix/netscaler gateway
- Source
- 50a63c94-1ea7-4568-8c11-eb79e7c5a2b5
EPSS moved from 0.3% on 4 October 2026 to 0.6% on 21 October 2026.
CISA notes
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. https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697174 ; https://community.citrix.com/techzone-blogs/110_security-updates/understanding-and-addressing-cve-2026-88779-in-citrix-netscaler-adc-and-citrix-netscaler-gateway/ ; 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-2026-88779
References
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697174Vendor Advisory
- https://community.citrix.com/techzone-blogs/110_security-updates/understanding-and-addressing-cve-2026-88779-in-citrix-netscaler-adc-and-citrix-netscaler-gateway/Mitigation, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-88779US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.