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Preparing for and Responding to CA Compromise and Fraudulent Certificate Issuance



Paul Turner, William Polk, Elaine B. Barker


As the use of Public Key Infrastructure (PKI) and digital certificates (e.g., the use of Transport Layer Security [TLS] and Secure Sockets Layer [SSL]) for the security of systems has increased, the certification authorities (CAs) that issue certificates have increasingly become targets for sophisticated cyber-attacks. In 2011, several public certification authorities were attacked, and at least two attacks resulted in the successful issuance of fraudulent certificates by the attackers. An attacker who breaches a CA to generate and obtain fraudulent certificates does so to launch further attacks against other organizations or individuals. An attacker can also use fraudulent certificates to authenticate as another individual or system, or to forge digital signatures.
ITL Bulletin -


certificates, certification authorities (CAs), digital certificates, fraudulent, Public Key Infrastructure (PKI)


Turner, P. , Polk, W. and Barker, E. (2012), Preparing for and Responding to CA Compromise and Fraudulent Certificate Issuance, ITL Bulletin, National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 18, 2024)


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Created July 9, 2012, Updated October 12, 2021