Iframes can pose significant security risks, including Cross-Site Scripting (XSS), clickjacking, Cross-Frame Scripting (CFS) attacks, session hijacking, phishing and social engineering attacks, and data privacy risks. Iframes create a parent-child relationship between the hosting page and the content inside the iframe, which can be exploited by malicious actors. Embedding login forms or sensitive data entry forms in iframes increases the risk of phishing attacks, compromising user security. To mitigate these risks, developers should use security best practices such as setting proper HTTP headers, validating sources, using HTTPS, enforcing same-origin policy, implementing Content Security Policy (CSP), and regularly auditing embedded content.