---
title: "CVE-2026-88772: Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-88772/
description: "CVE-2026-88772 (Citrix NetScaler): Exploited in the wild (CISA KEV). Vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-09-27
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-88772"
kev: true
cvss: 9.5
epss: 0.01301
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-88772: Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Citrix NetScaler. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-09-27, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-09-30 ; treat that as the outer limit, not the target.
- EPSS 1.3% , percentile 70: FIRST’s model estimates a 1.3% chance of exploitation activity in the next 30 days, higher than 70% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Editorial verdict: Act now. NetScaler CVE-2026-88771/88772: Exploited Pre-Auth RCE — Every customer-managed NetScaler ADC or Gateway needs the latest build today, and any appliance that was unpatched in September should be investigated as compromised, because patching does not evict attackers.

## What it is

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 (CVE record)

- Citrix NetScaler ADC: < 14.1-73.37, < 13.1-64.23, < 14.1-73.37 FIPS, < 13.1.37.279 FIPS and NDcPP
- Citrix NetScaler Gateway: < 14.1-73.37, < 13.1-64.23

## Severity

- NetScaler CVSS 4.0: 9.5 `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`

## Exploitation

- CISA KEV: added 2026-09-27; federal due date 2026-09-30. Known ransomware use: Unknown.
- CISA 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.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 1.30% probability of exploitation activity in the next 30 days; percentile 70.

## Sources

- [Listed in CISA KEV notes (community.citrix.com)](https://community.citrix.com/techzone-blogs/110_security-updates/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve-2026-88771-through-cve-2026-88778)
- [Listed in CISA KEV notes (support.citrix.com)](https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096)
- [Listed in CISA KEV notes (support.citrix.com)](https://support.citrix.com/external/article/CTX694799/steps-to-take-if-netscaler-adc-is-suspec.html)
- [CVE.org record CVE-2026-88772](https://www.cve.org/CVERecord?id=CVE-2026-88772)
- [NVD entry CVE-2026-88772](https://nvd.nist.gov/vuln/detail/CVE-2026-88772)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-88772)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk)
- [support.citrix.com](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)

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Source page: https://erroneo.us/security/cve/CVE-2026-88772/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt