Report vulnerabilities privately through GitHub security advisories for futhr/letterpress. Do not open a public issue containing an exploit, template source, recipient data, credentials, or unpublished artifact details.

Letterpress treats template source and render values as untrusted input. Its allow-lists, compiler process boundary, canonical artifacts, strict Liquid runtime, and resource budgets are security controls. Node permission mode is defense in depth rather than a sandbox. Consumers remain responsible for author authorization, tenant isolation, provider policy, and workload isolation.

Supported releases receive security fixes.