← West Pharmaceutical Services

2026 West Pharmaceutical Services — ransomware; data exfiltration and encrypted systems (May)

2026 Unknown records affected Share on X

Data compromised

Undisclosed categories at catalog time—company confirmed data theft and system encryption; no attested individual count in SEC summary

Technical writeup

West Pharmaceutical Services, Inc. (NYSE: WST), a U.S. S&P 500 contract drug-packaging and delivery manufacturer, disclosed a material May 2026 cybersecurity attack: unauthorized parties exfiltrated data and encrypted certain systems after intrusion detection on May 4 and materiality confirmation on May 7. West took systems offline globally, notified law enforcement, and engaged Palo Alto Networks Unit 42. By May 20, 2026 Reuters reported West was fully operational across manufacturing, supply chain, and commercial sites with no expected material impact on 2026 financial guidance, while forensic review—including assessing how much data may have been affected—remained ongoing. BleepingComputer noted partial recovery earlier in the month. No consolidated victim count or detailed data categories had been published in indexed English trade press at catalog time.

Root cause

Ransomware-style attack with data exfiltration and encryption of portions of on-premise infrastructure

References