Softwaresignaturen

SoftwareSignaturen, or software signatures, is a term describing digital signatures applied to software artifacts to verify authorship and integrity. A software signature is created by applying a private cryptographic key to the artifact or its metadata, producing a signature that can be verified with a corresponding public key and a trusted certificate. Signatures are commonly used on installers, libraries, updates, containers, and source-code releases to assure users that the software has not been tampered with since it was signed and that it comes from a legitimate publisher.

Verification typically involves checking the signature against a trusted chain of certificates stored in the operating system, package manager, or development environment. If the signature is valid and the chain trusted, the artifact is allowed to install or run; otherwise, it is blocked or flagged.

Common implementations include code signing on Windows (AuthentiCode) and macOS (codesign with notarization), Android APK signing, and iOS app signing, and Linux package signing with GnuPG or vendor-specific tools. Container images and artifacts can be signed with systems such as sigstore/cosign or The Update Framework (TUF). Formats and standards involved include X.509 certificates, PKI, CMS/PKCS7, and PGP.

Key management is a central concern: safeguarding private signing keys, cert renewal, key rotation, and revocation. Additional considerations include timestamping to prove signing time, reproducible builds for auditing, and protecting the integrity of the signing workflow to prevent supply-chain attacks.