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Microsoft's RC4 Encryption Vulnerability Exploited in Black Basta Ransomware Attack on Ascension

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📰 2 unique sources, 2 articles

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U.S. Senator Ron Wyden has called for an FTC investigation into Microsoft's cybersecurity practices, citing the company's support for RC4 encryption and insecure default settings that facilitated a ransomware attack on the Ascension healthcare network. The attack, attributed to the Black Basta ransomware group, compromised nearly 5.6 million individuals' personal and medical information. The breach occurred when a contractor's system was infected via a malicious link on Microsoft's Bing search engine. Attackers exploited insecure default settings and Kerberoasting techniques to gain elevated access to Ascension's network. Microsoft has acknowledged the vulnerabilities and plans to deprecate RC4 support in future updates. Wyden has criticized Microsoft for not clearly warning customers about the risks associated with RC4 encryption and for not taking decisive action to mitigate security risks.

Timeline

  1. 11.09.2025 22:23 📰 1 articles · ⏱ 5d ago

    Senator Wyden Requests FTC Investigation into Microsoft's Cybersecurity Practices

    U.S. Senator Ron Wyden has requested an FTC investigation into Microsoft's cybersecurity practices, citing the company's support for RC4 encryption and insecure default settings that facilitated the Black Basta ransomware attack on the Ascension healthcare network. Wyden criticized Microsoft for not clearly warning customers about the dangers of using RC4 encryption and for not taking decisive action to mitigate security risks. Microsoft has engaged with Wyden's office and plans to gradually remove RC4 support to avoid disrupting customer systems.

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  2. 11.09.2025 17:51 📰 2 articles · ⏱ 6d ago

    Black Basta Ransomware Exploits Microsoft's RC4 Encryption in Healthcare Breach

    The Black Basta ransomware group exploited insecure default settings and RC4 encryption in Microsoft software to gain access to Ascension's network. The attack, which occurred when a contractor clicked on a malicious Bing Search result in Microsoft Edge, compromised nearly 5.6 million individuals' personal and medical information. Microsoft has acknowledged the vulnerabilities and plans to deprecate RC4 support in future updates. Wyden has criticized Microsoft for not clearly warning customers about the risks associated with RC4 encryption and for not taking decisive action to mitigate security risks.

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