Cisco (CSCO) Stock After Hours Today (Dec. 19, 2025): What Investors Need to Know Before the Next Market Open
Cisco shares closed at $78.42 Friday, up 1.9%, and held steady after hours amid heavy trading volume of about 84 million shares tied to major derivatives expiration. Investors are watching a critical, actively exploited vulnerability in Cisco’s Secure Email products, with the company confirming ongoing cyberattacks targeting certain appliances. U.S. markets reopen Monday, with cybersecurity risks in focus.