Application programming interfaces (APIs) have become a central part of the modern IT environment, allowing developers to enrich the functionality of applications and interact with third parties such as cloud and payment providers. This interaction often occurs through authentication mechanisms that rely on sensitive credentials such as API keys and tokens that require secure handling. Exposure of these credentials can pose significant consequences to organizations, as malicious attackers can gain access to related services. Previous studies have shown exposure of these sensitive credentials in different environments such as cloud platforms and GitHub. However, the web remains unexplored. In this paper, we study exposure of credentials on the web by analyzing 10M webpages. Our findings reveal that API credentials are widely and publicly exposed on the web, including highly popular and critical webpages such as those of global banks and firmware developers. We identify 1,748 distinct credentials from 14 service providers (e.g., cloud and payment providers) across nearly 10,000 webpages. Moreover, our analysis of archived data suggest credentials to remain exposed for periods ranging from a month to several years. We characterize web-specific exposure vectors and root causes, finding that most originate from JavaScript environments. We also discuss the outcomes of our responsible disclosure efforts that demonstrated a substantial reduction in credential exposure on the web.

翻译：应用程序编程接口（API）已成为现代IT环境的核心组成部分，使开发者能够增强应用程序功能并与云服务和支付提供商等第三方进行交互。此类交互通常通过依赖敏感凭证（如API密钥和令牌）的身份验证机制实现，这些凭证需要安全处理。一旦这些凭证暴露，可能对组织造成严重后果，恶意攻击者可借此访问相关服务。先前研究表明，此类敏感凭证已在云平台和GitHub等不同环境中存在暴露现象。然而，网络环境中的暴露情况尚未得到充分探索。本文通过分析1000万个网页，研究了网络环境中的凭证暴露问题。我们的研究结果表明，API凭证在网络中被广泛公开暴露，涉及全球性银行和固件开发商等高度流行且关键性强的网页。我们在近1万个网页中识别出来自14家服务提供商（如云服务和支付提供商）的1748个独立凭证。此外，对存档数据的分析表明，这些凭证的暴露时间可持续从一个月到数年不等。我们系统分析了网络特有的暴露途径和根本原因，发现大多数暴露源自JavaScript环境。本文还探讨了负责任披露工作的成果，证明该措施能显著减少网络中的凭证暴露现象。