Comcast has confirmed that hackers exploiting a critical-rated security vulnerability accessed the sensitive information of almost 36 million Xfinity customers.

This vulnerability, known as “CitrixBleed,” is found in Citrix networking devices often used by big corporations and has been under mass-exploitation by hackers since late August. Citrix made patches available in early October, but many organizations did not patch in time. Hackers have used the CitrixBleed vulnerability to hack into big-name victims, including aerospace giant Boeing, the Industrial and Commercial Bank of China, and international law firm Allen & Overy.

Comcast's statement

Notice To Customers of Data Security Incident
December 18, 2023 04:30 PM Eastern Standard Time

PHILADELPHIA--(BUSINESS WIRE)--Xfinity is providing notice of a recent data security incident. Starting today, customers are being notified through a variety of channels, including through the Xfinity website, email, and news media.

On October 10, 2023, Citrix announced a vulnerability in software used by Xfinity and thousands of other companies worldwide. Citrix issued additional mitigation guidance on October 23, 2023. Xfinity promptly patched and mitigated the Citrix vulnerability within its systems. However, during a routine cybersecurity exercise on October 25, Xfinity discovered suspicious activity and subsequently determined that between October 16 and October 19, 2023, there was unauthorized access to its internal systems that was concluded to be a result of this vulnerability.

Xfinity notified federal law enforcement and initiated an investigation into the nature and scope of the incident. On November 16, Xfinity determined that information was likely acquired. After additional review of the affected systems and data, Xfinity concluded on December 6, 2023, that the customer information in scope included usernames and hashed passwords; for some customers, other information may also have been included, such as names, contact information, last four digits of social security numbers, dates of birth and/or secret questions and answers. However, the data analysis is continuing.

Xfinity has required customers to reset their passwords to protect affected accounts. In addition, Xfinity strongly recommends that customers enable two-factor or multi-factor authentication to secure their Xfinity account, as many Xfinity customers already do. While Xfinity advises customers not to re-use passwords across multiple accounts, the company is recommending that customers change passwords for other accounts for which they use the same username and password or security question.

Customers with questions can contact Xfinity’s dedicated call center at 888-799-2560 toll-free 24 hours a day, seven days a week. More information is available on the Xfinity website at www.xfinity.com/dataincident.

Customers trust Xfinity to protect their information, and the company takes this responsibility seriously. Xfinity remains committed to continued investment in technology, protocols and experts dedicated to helping to protect its customers.