# User Privacy Protection Cheat Sheet — Digital Certificate Pinning

> Certificate Pinning is the practice of hardcoding or storing a predefined set of information (usually hashes) for digital certificates/public keys in the user agent (be it web browser, mobile app or browser plugin) such that only the predefined certificates/public keys are used for secure communicat

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-owasp-9f8598d9eaed43dd154b>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:05.047485+00:00`
- Tags: `reference-seed`, `owasp`, `cheatsheets`, `user`, `privacy`, `protection`, `cheat`, `sheet`, `digital`, `certificate`, `pinning`

## Provenance

- Source: <https://github.com/OWASP/CheatSheetSeries/blob/07111ee754e832e335377ac64fd0f8f848d9029c/cheatsheets/User_Privacy_Protection_Cheat_Sheet.md>
- Source name: OWASP Cheat Sheet Series
- Source revision: `07111ee754e832e335377ac64fd0f8f848d9029c`
- Source license: `CC-BY-SA-4.0`
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## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Certificate Pinning is the practice of hardcoding or storing a predefined set of information (usually hashes) for digital certificates/public keys in the user agent (be it web browser, mobile app or browser plugin) such that only the predefined certificates/public keys are used for secure communication, and all others will fail, even if the user trusted (implicitly or explicitly) the other certificates/public keys.

Some advantages for pinning are

In the event of a CA compromise, in which a compromised CA trusted by a user can issue certificates for any domain, allowing evil perpetrators to eavesdrop on users. In environments where users are forced to accept a potentially-malicious root CA, such as corporate environments or national PKI schemes. In applications where the target demographic may not understand certificate warnings, and is likely to just allow any invalid certificate.

For details regarding certificate pinning, please refer to the following

OWASP Certificate Pinning Cheat Sheet. Public Key Pinning Extension for HTTP RFC. Securing the SSL channel against man-in-the-middle attacks: Future technologies - HTTP Strict Transport Security and Pinning of Certs, by Tobias Gondrom.

Attribution: Adapted from OWASP Cheat Sheet Series under CC-BY-SA-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.