CISA ordered federal agencies to patch Citrix NetScaler appliances for CVE-2026-3055 by April 2. The flaw lets unauthenticated attackers steal admin SAML session IDs from NetScaler ADC and Gateway devices configured as SAML identity providers, which can enable full takeover of unpatched appliances. Citrix released fixes March 23 and researchers reported active exploitation days later; Shadowserver lists tens of thousands of NetScaler instances exposed online.
CISA tells federal agencies to patch Citrix NetScaler bug by Thursday
The bug enables threat actors to send requests that disclose sensitive information and carries a severity score of 9.3 out of 10, indicating a critical risk.
CISA orders feds to patch actively exploited Citrix flaw by Thursday
Cybersecurity and Infrastructure Security Agency (CISA) ordered government agencies to patch their Citrix NetScaler appliances against an actively exploited vulnerability by Thursday.