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Bug Bounty Discoveries: Critical Vulnerabilities in Web Applications

bug bountyexploitvulnerabilityweb applicationserver-side
Updated October 31, 2025 at 10:00 PM3 sources

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Security researchers uncovered several critical vulnerabilities in popular web applications through bug bounty programs, demonstrating the risks posed by insecure coding practices and insufficient input validation. One researcher found a flaw in a car-parts marketplace that allowed manipulation of a URL parameter to set product prices to zero, exploiting a backend logic error where an invalid id_product_feature_set parameter defaulted the price to zero. Another report detailed a $1,000 bounty for a GitLab GraphQL API vulnerability that enabled project maintainers to delete entire repositories, bypassing intended permission restrictions and highlighting the importance of robust access control in API design.

Additionally, a researcher discovered a $10,000 vulnerability in Shopify's Return Magic app, where a Handlebars template injection in customizable email templates could lead to server-side code execution, potentially allowing full server takeover. These incidents underscore the value of bug bounty programs in identifying and mitigating high-impact security flaws before they can be exploited by malicious actors, and they emphasize the need for secure development practices, thorough code review, and regular security testing in web applications.

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