CVE-2026-88778 (GCVE-0-2026-88778)

Vulnerability from cvelistv5 – Published: 2026-09-27 16:43 – Updated: 2026-09-29 16:35
VLAI
Title
TCP Initial Sequence Number (ISN) prediction
Summary
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.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:L/SI:L/SA:L
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 16:34 UTC
CWE
  • CWE-342 - Predictable exact value from previous values
Assigner
NetScaler CNA under the mitre root
CNA scorecard C 63/100 over 18 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Citrix NetScaler ADC Affected: 0 , < 14.1-73.37 (Patch)
Affected: 0 , < 13.1-64.23 (Patch)
Affected: 0 , < 14.1-73.37 FIPS (Patch)
Affected: 0 , < 13.1.37.279 FIPS and NDcPP (Patch)
guessed Create a notification for this product.
Citrix NetScaler Gateway Affected: 0 , < 14.1-73.37 (Patch)
Affected: 0 , < 13.1-64.23 (Patch)
guessed Create a notification for this product.
Date Public
2026-09-27 15:30
Show details on NVD website
To clipboard 

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  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.