CVE-2026-88778

TCP Initial Sequence Number (ISN) prediction

HIGH

7.5

CVSS Score

Published: September 27, 2026 at 04:43 PM UTC

Updated: September 29, 2026 at 05:17 PM UTC

3 products affected across 2 vendorsNetScaler GatewayNetscaler Application Delivery ControllerNetScaler ADC

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Severity

HIGH7.5

Exploit prediction

EPSS 0.7%

SSVC

No known exploit

Description

Predictable exact value from previous values 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Netscaler Application Delivery Controller · Citrix

95%

13.1 ≤ v < 13.1-64.2313.1 ≤ v < 13.1.37.27914.1 ≤ v < 14.1-73.3714.1-66.68 ≤ v ≤ 14.1-73.37

Affected range stops below 13.1-64.23, so it looks safe — our inference, not a vendor statement

Affected range stops below 13.1.37.279, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-73.37, so it looks safe — our inference, not a vendor statement

NetScaler Gateway · Citrix

95%

v < 13.1-64.23v < 14.1-73.3713.1 ≤ v < 13.1-64.2314.1 ≤ v < 14.1-73.37

Affected range stops below 13.1-64.23, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-73.37, so it looks safe — our inference, not a vendor statement

NetScaler ADC · Citrix Netscaler

60%

v < 13.1-64.23v < 13.1.37.279 FIPS and NDcPPv < 14.1-73.37v < 14.1-73.37 FIPS

Affected range stops below 13.1-64.23, so it looks safe — our inference, not a vendor statement

Affected range stops below 13.1.37.279 FIPS and NDcPP, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-73.37, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-73.37 FIPS, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096

References (1)

Vendor Advisory

Source: cverecord

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096

SSVC — Action Prioritization

SSVCNo known exploitAutomatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGH[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: NONE
Availability: NONE

Vector?

Quick Info

StatusANALYZED

CWE

CWE-342

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