Hackers breached the security of over 35 million Xfinity users' accounts by taking advantage of a critical-rated vulnerability, according to Comcast.

In late August, hackers began exploiting a vulnerability called "CitrixBleed" in Citrix networking equipment, which is often employed by large organizations.

Many firms failed to apply the updates in time despite Citrix making them accessible in early October.

In a report by TechCrunch, notable victims that have fallen prey to hackers using the CitrixBleed vulnerability include the Industrial and Commercial Bank of China, global law firm Allen & Overy, and aerospace giant Boeing.

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In this photo illustration, A Comcast logo is displayed at Comcast Center on April 13, 2021, in Philadelphia, Pennsylvania.

Xfinity Hit by 'Citrixbleed' Security Flaw

Xfinity, the cable television and internet division of Comcast, was the most recent target of CitrixBleed, according to the company's notice to customers on Monday, December 18.

The American telecom behemoth revealed that no malicious activity was detected until October 25. Reportedly, the hackers already gained access to its internal systems from October 16 to 19 via the CitrixBleed vulnerability.

Xfinity discovered on November 16 that the hackers had likely obtained some information. This month, the business came to the conclusion that this contained client data, such as passwords and usernames, which are kept in a manner that renders them unintelligible to humans.

The business has announced that hackers may have gained access to sensitive information for an undetermined number of clients, including names, contact details, dates of birth, Social Security numbers (down to the last four digits), and security questions and answers.

According to Comcast, "Our data analysis is continuing, and we will provide additional notices as appropriate," which might mean that other kinds of data were also accessed.

See Also: British Library Hit by Data Breach, Potentially Causing Months of Disruption

Instructions for Millions Affected by Breach

The notification does not specify the number. Nevertheless, Comcast verified in a document sent to the attorney general of Maine that the breach impacted about 35.8 million subscribers. The fact that more than 32 million broadband subscribers are included in Comcast's most recent financial report implies that this breach has affected the majority, if not all, of Xfinity customers.

The fate of Xfinity, the effects on the company's operators, and whether or not the event has been reported to the United States Securities and Exchange Commission (SEC) in accordance with the regulator's new data breach reporting regulations are yet unknown. But Comcast spokesperson Joel Shadle told TechCrunch, "We are not aware of any customer data being leaked anywhere, nor of any attacks on our customers."

Xfinity has announced that it would be mandating password resets and strongly suggests that all user accounts utilize two-factor or multi-factor authentication, even though the firm does not mandate it by default.

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