Cloud Security Stocks Plunge 6% After Guidance Shock, 2 Trillion Won Vanishes in a Day

Cloud security provider Zscaler Inc. (NASDAQ: ZS) closed at $145.51 on June 2, down 6.55%, wiping out roughly $1.45 billion in market value—about ₩2 trillion—in a single day. Trading volume reached approximately 6.06 million shares, markedly above its norm. Its current market capitalization stands at about $23.5 billion (around ₩32 trillion).

After issuing fourth-quarter revenue guidance below analysts’ expectations, Zscaler’s stock tumbled nearly 30% the day after its earnings release, triggering a “guidance shock.” Legal risks have also surfaced, with several law firms launching investigations into potential investor losses. Nevertheless, Wall Street continues to issue buy ratings, citing roughly 25% upside potential and arguing that the sell-off is an overreaction.

Founded in 2008 and headquartered in San Jose, California, Zscaler specializes in cloud-based security, protecting corporate internet and application access through Zero Trust Network Access (ZTNA) and Security Service Edge (SSE) solutions. Led by founder and CEO Jay Chaudhry, the company is now targeting AI-era security demand with new offerings such as GPT-5.5-Cyber and “Project AI-Guardian.”