Windows Zero-Days Expose BitLocker Bypass, CTFMON Privilege Escalation

An anonymous cybersecurity researcher, operating under the alias Chaotic Eclipse, has disclosed two new Windows zero-day vulnerabilities. These critical flaws include a BitLocker bypass, codenamed YellowKey, and a privilege escalation impacting the Windows Collaborative Translation Framework (CTFMON), dubbed GreenPlasma, according to The Hacker News.

These disclosures follow the researcher’s previous findings of three Microsoft Defender vulnerabilities. The BitLocker bypass is particularly concerning, as it directly undermines a fundamental data protection control. A successful exploit would allow an attacker to circumvent disk encryption, exposing sensitive data to unauthorized access. The CTFMON privilege escalation, on the other hand, could enable an attacker to elevate their access from a low-privileged user to a system-level account, granting them extensive control over the compromised machine.

For defenders, these zero-days highlight the persistent challenge of securing core Windows components. Attackers are relentlessly probing for cracks in foundational security mechanisms. The ability to bypass BitLocker or gain SYSTEM privileges through CTFMON provides significant leverage for post-exploitation activities, including data exfiltration, lateral movement, and persistence.