MRZ means machine-readable zone: the encoded lines printed on passports and many travel documents. These lines contain standardized identity data such as the document number, name, nationality, date of birth, and an expiration check. Border systems and identity verification tools read the MRZ first because it is fast, consistent, and easy to validate with built-in checksums.
In cyber security, MRZ data matters because it is often collected in document theft, phishing, and scam workflows that target identity verification. If attackers obtain passport images or MRZ strings, they can use them to build convincing fake onboarding attempts, bypass weak KYC checks, or combine them with other records for identity fraud. Defenders protect MRZ-bearing documents with strict access controls, encryption, redaction, and monitoring for unusual exports or uploads of passport images.