Microsoft patches Windows BitLocker vulnerability.gettyPassword theft, by the billion, has been in the news recently, as has Microsofts desire to replace the security measure for all users. Security experts have now warned that a vulnerability impacting Microsofts Windows BitLocker encryption system could expose sensitive data, including your passwords, in unencrypted form. Heres what you need to know and do to stay safe.Microsoft Confirms Windows BitLocker Security VulnerabilityThe latest Microsoft Patch Tuesday security rollout on Jan. 14 hit the headlines for two reasons this month: three Windows zero-day vulnerabilities already being exploited by attackers and the sheer number of security issues confirmed in the security update itself. Among the 159 vulnerabilities listed as patched by Microsoft was one that somehow managed to avoid too much media attention. Lets put that right by looking at it through the eyes of two security experts as its actually a pretty nasty one that could expose unencrypted data by exploiting an issue with how Windows BitLocker stores hibernation images in RAM.Microsoft itself called CVE-2025-21210 a Windows BitLocker information disclosure vulnerability, one that could allow the disclosure of unencrypted hibernation images in cleartext. So, what does that actually mean beyond the silent screaming of Windows users everywhere? Who better to ask than security professionals who know this stuff inside out?What Security Experts Say About The Microsoft BitLocker ThreatCVE-2025-21210, flagged as exploitation more likely by Microsoft, targets the Windows full disk encryption system, BitLocker. It is designed to keep your device secure offline, preventing threat actors with physical access from accessing any potentially sensitive data. This vulnerability, Kev Breen, senior director of threat research at Immersive Labs, said, suggests that in some situations, hibernation images may not be fully encrypted and could be recovered in plain text. Hibernation images are used when your laptop enters sleep mode, containing whatever contents were in RAM as it powered down. This presents a significant potential impact, Breen warned, as RAM can contain sensitive data such as passwords, and credentials, that may have been in open documents or browser sessions and can all be recovered with free tools from hibernation files.Meanwhile, Dr Marc Manzano, general manager of cybersecurity at SandboxAQ, said, "The recent Windows BitLocker vulnerability exposing AES-XTS encryption highlights the critical need for modern cryptography management solutions deployed at scale across IT infrastructures. Solutions that, Manzano advised, should allow for the adjustment of encryption policies and implementation of updates swiftly, minimizing exposure to emerging threats. Without these capabilities, Manzano concluded, businesses risk leaving vulnerabilities unaddressed, exposing sensitive data to potential exploits.MORE FOR YOUMitigating The Microsoft BitLocker RiskBreen conceded that there is an important caveat to be attached to the BitLocker vulnerability exploit threat: physical access to the device is likely to be required, meaning laptop theft is the most likely source for threat actors to obtain devices.Indeed, Microsoft said that an attacker needs repeated physical access to the victim machine's hard disk. All of that said, its hard to disagree with Breen who concluded that if you have users with sensitive data traveling often, then this should be a high priority to patch. So, if you havent applied the latest Patch Tuesday fixes as of yet, now is the time to act.I have reached out to Microsoft for a statement.