CVE-2026-88775: Memory overflow vulnerability leading to unpredictable or erroneous behavior or Denial of Service

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-27 · updated 2026-09-29
Weakness: CWE-120

Description

Memory overflow 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 Memory overflow vulnerability leading to unpredictable or erroneous behavior or Denial of Service

Summary

CVE-2026-88775 is a critical (CVSS 9.8) memory overflow in Citrix NetScaler ADC and NetScaler Gateway that can cause unpredictable or erroneous behavior or a denial of service. Affected versions are 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, and Gateway before 14.1-73.37 and before 13.1-64.23. It is not in CISA KEV and SSVC reports no known exploitation, with EPSS at 0.7%. Upgrade to the fixed versions: ADC 13.1-64.23, 13.1.37.279, or 14.1-73.37, and Gateway 13.1-64.23 or 14.1-73.37.

CVE-2026-88775 ثغرة تجاوز سعة الذاكرة حرجة (CVSS 9.8) في Citrix NetScaler ADC وNetScaler Gateway، وقد تؤدي إلى سلوك غير متوقع أو خاطئ أو حجب الخدمة. تشمل الإصدارات المتأثرة ADC قبل 14.1-73.37 وقبل 13.1-64.23 وقبل 14.1-73.37 FIPS وقبل 13.1.37.279 FIPS وNDcPP، وGateway قبل 14.1-73.37 وقبل 13.1-64.23. الثغرة ليست في CISA KEV ولا يشير SSVC إلى أي استغلال معروف، واحتمال الاستغلال خلال 30 يوماً وفق EPSS هو 0.7%. يُنصح بالترقية إلى الإصدارات المُصلحة: ADC 13.1-64.23 أو 13.1.37.279 أو 14.1-73.37، وGateway 13.1-64.23 أو 14.1-73.37.

Affected products

Citrix NetScaler ADC: from 13.1 before 13.1-64.23; from 14.1 before 14.1-73.37 — fixed in 13.1-64.23, 14.1-73.37
Citrix Netscaler Application Delivery Controller Fips: from 13.1 before 13.1.37.279; from 14.1-66.68 through 14.1-73.37 — fixed in 13.1.37.279
Citrix Netscaler Application Delivery Controller Ndcpp: from 13.1 before 13.1.37.279 — fixed in 13.1.37.279
Citrix NetScaler Gateway: from 13.1 before 13.1-64.23; from 14.1 before 14.1-73.37 — fixed in 13.1-64.23, 14.1-73.37
NetScaler ADC: before 14.1-73.37; before 13.1-64.23; before 14.1-73.37 FIPS; before 13.1.37.279 FIPS and NDcPP — fixed in 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, 13.1.37.279 FIPS and NDcPP
NetScaler Gateway: before 14.1-73.37; before 13.1-64.23 — fixed in 14.1-73.37, 13.1-64.23

How to fix

Upgrade to a fixed version: Citrix NetScaler ADC 13.1-64.23, 14.1-73.37; Citrix Netscaler Application Delivery Controller Fips 13.1.37.279; Citrix Netscaler Application Delivery Controller Ndcpp 13.1.37.279; Citrix NetScaler Gateway 13.1-64.23, 14.1-73.37; NetScaler ADC 14.1-73.37, 13.1-64.23, 14.1-73.37 FIPS, 13.1.37.279 FIPS and NDcPP; NetScaler Gateway 14.1-73.37, 13.1-64.23. Check the vendor advisory for mitigations.

In the news

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

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