---
title: "CVE-2026-88779: Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-88779/
description: "CVE-2026-88779 (Citrix NetScaler): Exploited in the wild (CISA KEV). Vulnerability in NetScaler ADC and NetScaler Gateway. This issue affects ADC: before…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-04
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-88779"
kev: true
cvss: 8.7
epss: 0.00592
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-88779: 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 2026-10-04, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-10-07 ; treat that as the outer limit, not the target.
- EPSS 0.6% , percentile 48: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 48% of all scored CVEs (low). 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 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.

## Affected products (CVE record)

- NetScaler ADC: < 14.1-73.41, < 13.1-64.28, < 14.1-73.41 FIPS, < 13.1-37.282
- NetScaler Gateway: < 14.1-73.41, < 13.1-64.28

## Severity

- NetScaler CVSS 4.0: 8.7 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: added 2026-10-04; federal due date 2026-10-07. 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 yes , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.59% probability of exploitation activity in the next 30 days; percentile 48.

## Sources

- [community.citrix.com](https://community.citrix.com/techzone-blogs/110_security-updates/understanding-and-addressing-cve-2026-88779-in-citrix-netscaler-adc-and-citrix-netscaler-gateway/)
- [Listed in CISA KEV notes (support.citrix.com)](https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697174)
- [CVE.org record CVE-2026-88779](https://www.cve.org/CVERecord?id=CVE-2026-88779)
- [NVD entry CVE-2026-88779](https://nvd.nist.gov/vuln/detail/CVE-2026-88779)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-88779)
- [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)

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Source page: https://erroneo.us/security/cve/CVE-2026-88779/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt