Risk Letters

Exploited vulnerability

CVE-2026-88771

TLP:CLEAR

Citrix NetScaler Improper Input Validation Vulnerability

Citrix NetScaler ADC and NetScaler Gateway contain an improper input validation vulnerability that could allow an unauthenticated attacker to execute arbitrary commands.

Facts

  • Vendor: Citrix
  • Product: NetScaler
  • CVSS: 9.8
  • EPSS (probability of exploitation within 30 days): 82.2 %
  • On CISA's Known Exploited Vulnerabilities list since: 27 September 2026
  • First known exploitation: 27 September 2026
  • CISA's deadline for US federal agencies: 30 September 2026
  • Weakness: CWE-119
  • First seen by Risk Letters: 27 September 2026

Members see which Nordic sectors the flaw hits, and what to do about it.

Get the full brief

Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD