[Cyber Security Terms](/glossary) Data Leak [Blog](/blog)[Breaches](/breaches)[Resources](/resources)[News](/news) [Cyber Security Terms](/glossary) # Data Leak ##### [Edward Kost](/team/edward-kost) updated Jul 09, 2025 ###### Contents ## What is a Data Leak? A data leak is an overlooked exposure of sensitive data usually occurring through a software vulnerability. Data leaks can also be physical, like login credentials written on a post-it note. Any vector that facilitates unmitigated access to sensitive resources is considered a data leak. The most critical category of data leaks is customer [Personal Identifiable Information (PII)](https://www.upguard.com/blog/personally-identifiable-information-pii) because their compromise could expose customers to further cyberattacks and data breaches. Data leaks, if left unaddressed, could develop into data breaches if they’re discovered by cybercriminals. This is why the [timely detection and remediation of data leaks](https://www.upguard.com/product/breach-risk/threat-monitoring) should be a primary component of data breach prevention strategies. ## Data Leak Examples Data leaks most commonly occur through software vulnerabilities and misconfigurations. Other examples of data leaks include: * Zero-day exploits * Unsecured databases * Poor access management. * Unsecured endpoints. * Software errors. * Careless employee practices. * System Errors. Each of these events create perforations in cybersecurity programs, giving cybercriminals seamless access to sensitive resources. One of the most famous examples of a data leak was the [Microsoft Power App exposure](https://www.upguard.com/breaches/power-apps#toc-discovery). By default OData (Open Data Protocol) APIs were disabled, allowing public access sensitive Power Apps databases. UpGuard researchers discovered the data leak exposing up to 38 million records and notified Microsoft, preventing a potentially catastrophic data breach ## What’s the Difference Between a Data Leak and a Data Breach? The primary [difference between a data leak and a data breach](https://www.upguard.com/blog/data-leak-prevention-tips) is whether or not the data exposure was initiated by cybercriminals. A data breach is the intended outcome of a planned cyber attack, but a data leak is an unintentional pathway to sensitive resources through a security loophole. Unlike data breaches, data leaks usually stem from internal negligence. ## Key takeaways * Data leaks, unlike data breaches, are commonly initiated by internal errors. * Data leaks could develop into data breaches if they're discovered by cybercriminals. * A data breach prevention strategy should be approached through a data leak mitigation perspective. * * ###### Reviewed by No items found. ###### Author ##### [Edward Kost](/team/edward-kost) ###### Reviewed by ##### [Kaushik Sen](/team/kaushik-sen) ###### Join 27,000+ cybersecurity newsletter subscribers ## Read more about Data Leaks Learn more about Data Leak and the latest issues in cybersecurity. [UpGuard](/blog/downstream-data-investigating-ai-data-leaks-in-flowise) [Downstream Data: Investigating AI Data Leaks in Flowise](/blog/downstream-data-investigating-ai-data-leaks-in-flowise) #### [Downstream Data: Investigating AI Data Leaks in Flowise](/blog/downstream-data-investigating-ai-data-leaks-in-flowise) A thousand Flowise instances are exposed to the internet, many of them leaking confidential business data, passwords, and more. [](/team/greg-pollock) [Greg Pollock](#) October 21, 2026 [UpGuard](/blog/llama-cpp-prompt-leak) [Analyzing llama.cpp Servers for Prompt Leaks](/blog/llama-cpp-prompt-leak) #### [Analyzing llama.cpp Servers for Prompt Leaks](/blog/llama-cpp-prompt-leak) How are generative AI technologies leaking data? In this report we analyse prompt leaks from llama.cpp servers. [](/team/greg-pollock) [Greg Pollock](#) July 24, 2025 [UpGuard](/blog/how-to-reduce-false-positives-in-data-leak-detection) [How to Reduce False Positives in Data Leak Detection](/blog/how-to-reduce-false-positives-in-data-leak-detection) #### [How to Reduce False Positives in Data Leak Detection](/blog/how-to-reduce-false-positives-in-data-leak-detection) False positives are an inevitability in every data leak detection solution, but there are strategies you can implement to reduce them significantly. [](/team/edward-kost) [Edward Kost](#) October 21, 2026 [UpGuard](/blog/protecting-employee-credentials-from-ransomware-compromise) [The Ultimate Ransomware Defense Guide (2026)](/blog/protecting-employee-credentials-from-ransomware-compromise) #### [The Ultimate Ransomware Defense Guide (2026)](/blog/protecting-employee-credentials-from-ransomware-compromise) Learn how to implement an effective security strategy for minimizing the impact of ransomware attacks. [](/team/edward-kost) [Edward Kost](#) June 22, 2026 [UpGuard](/blog/how-finance-companies-can-prevent-data-leaks) [8 Ways Finance Companies Can Prevent Data Leaks](/blog/how-finance-companies-can-prevent-data-leaks) #### [8 Ways Finance Companies Can Prevent Data Leaks](/blog/how-finance-companies-can-prevent-data-leaks) Learn how data leaks are a high-risk cyber threat and eight ways your organizations can prevent data leaks in the finance industry. [](/team/catherine-chipeta) [Catherine Chipeta](#) October 21, 2026 [UpGuard](/blog/best-data-leak-detection-software-solutions) [Best Data Breach & Data Leak Detection Tools](/blog/best-data-leak-detection-software-solutions) #### [Best Data Breach & Data Leak Detection Tools](/blog/best-data-leak-detection-software-solutions) Stopping an intrusion is half the battle. This guide ranks the top breach and leak detection tools to neutralize exposed credentials before attackers do. [](/team/lance-turner) [Lance Turner](#) October 21, 2026 [View all blog posts](/blog) ## See UpGuard In Action Book a free, personalized onboarding call with one of our cybersecurity experts. [Contact sales](/demo) [Free demo](/demo) ## More from our blog Learn more about the latest issues in cybersecurity. [UpGuard](/blog/find-out-if-youre-exposed-on-the-dark-web) [Find Out if You're Exposed on the Dark Web](/blog/find-out-if-youre-exposed-on-the-dark-web) #### [Find Out if You're Exposed on the Dark Web](/blog/find-out-if-youre-exposed-on-the-dark-web) Answer 5 quick questions to predict what a dark web scan will find about your company. Then run the free scan to see your real exposure. 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[](/team/revashni-moodley) [Revashni Moodley](#) October 14, 2026 [UpGuard](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) [Good Security Rating? Your Dark Web Exposure Says Otherwise](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) #### [Good Security Rating? Your Dark Web Exposure Says Otherwise](/blog/good-security-rating-your-dark-web-exposure-says-otherwise) Scan your domain to see just how exposed you are on the Dark Web. [](/team/lance-turner) [Lance Turner](#) October 11, 2026 [View all blog posts](/blog) ### Sign up for our newsletter UpGuard's monthly newsletter cuts through the noise and brings you what matters most: our breaking research, in-depth analysis of emerging threats, and actionable strategic insights. ##### Free instant security score ## How secure is your organization? 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