A new flaw in Citrix NetScaler has been discovered, with exploit attempts reported in the wild. The vulnerability, compared to the previous CitrixBleed issue, is considered critical and has been exploited immediately after public disclosure. Citrix is urging administrators to patch the flaw as soon as possible, with some reports suggesting it may have been used as a zero-day exploit since May 2025, although details of the timeline and extent of exploitation are not entirely clear.