The newly discovered flaw in Microsoft's SharePoint software has allowed hackers to target dozens of companies and organizations. Only a partial fix has been issued.

Microsoft has issued an urgent alert after hackers began exploiting a critical SharePoint Server flaw. The FBI and CISA are responding as agencies and businesses are targeted.

Microsoft warned of "active attacks" targeting some users of its SharePoint software over the weekend and released an emergency patch that fixes only some versions of the vulnerable server software. Why it matters: It remains unclear how many businesses were already hacked prior to Microsoft's warning,