CISA adds Citrix NetScaler RCE vulnerabilities to KEV catalog
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Two Citrix NetScaler flaws enabling full system compromise are now confirmed actively exploited and prioritized for federal patching.
CISA has added CVE-2026-88771 and CVE-2026-88772 to its Known Exploited Vulnerabilities (KEV) Catalog based on evidence of active exploitation in the wild. Both are Citrix NetScaler vulnerabilities—the first an improper input validation flaw, the second a memory buffer bounds restriction issue—that grant attackers total control of affected systems post-exploitation. These are classified as high-risk and impact both federal civilian agencies under Binding Operational Directive (BOD) 26-04 and private-sector organizations. BOD 26-04 mandates federal agencies prioritize rapid remediation of KEV-listed vulnerabilities on publicly exposed assets and verify whether systems were compromised before patches were applied. CISA recommends all organizations adopt risk-based vulnerability management and treat these NetScaler flaws as priority patches. Defenders should immediately check for exposure, apply vendor patches, and conduct forensic review of systems accessible from the internet to determine prior compromise.
Mentioned in this report
Source reporting: https://www.cisa.gov/news-events/alerts/2026/09/27/cisa-adds-two-known-exploited-vulnerabilities-catalog
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