This article first appeared on GuruFocus.

Broadcom (NASDAQ:AVGO) shares dropped about 6% Friday as reports of attacks targeting a recently fixed VMware security issue weighed on the stock.

The vulnerability affects VMware vCenter Syslog Server, a tool used to manage and oversee virtual infrastructure. Broadcom disclosed the issue on July 29, describing it as a critical security weakness that could allow an outside attacker with network access to run unauthorized code.

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A report published Thursday said attackers are exploiting the flaw to install a reverse SSH tool, which can provide persistent remote access to compromised systems. Researchers identified 361 affected IP addresses across 47 countries, with Germany, the United States, Turkey, Iran and France accounting for more than half of the cases.

Digital forensics firm Quirso said affected systems began communicating with attacker-controlled infrastructure on Aug. 3, several days after Broadcom issued an emergency patch. The firm had identified the 361 victim addresses by Aug. 7.