Cybersecurity · head to head
Cosign vs Keil MDK
Cosign
Cybersecurity
Signs and verifies container images and artifacts, with or without managing keys
- From
- Free
- Free plan
- Yes
Keil MDK
Developer Tools
Microcontroller Development Kit for Arm-based devices
- From
- Free
- Free plan
- Yes
The short version
- Each has a real cost: Cosign keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.; Keil MDK pricing for Essential and Professional subscriptions not disclosed on primary site
- Prices and features above were last checked on 31 August 2026.
Where they differ
Only the attributes on which Cosign and Keil MDK actually diverge.
Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Cosign
- Keyless signing
- Key and KMS signing
- Registry-native storage
- In-toto attestations
- Offline verification
- Trusted root and signing config
Only in Keil MDK
Nothing recorded that Cosign does not also cover.
What people use each for
The jobs each tool is most often brought in to do.
Cosign
- Signing container images in a build pipeline without managing long-lived private keysnot Keil MDK
- Attaching a signed bill of materials to a release so consumers can verify its provenancenot Keil MDK
- Meeting a customer or regulatory requirement for signed artifactsnot Keil MDK
- Verifying third-party images before they enter an internal registrynot Keil MDK
Keil MDK
- Embedded software developmentnot Cosign
- ARM microcontroller programmingnot Cosign
- Professional development environmentsnot Cosign
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Cosign
- Keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.
- A signature proves who signed, never whether they should have. The documentation is explicit that Sigstore cannot determine authorisation, so every consumer must write and maintain their own identity and issuer policy or verification means nothing.
- Nothing is enforced without an admission controller. Signing changes what you can prove, not what runs, and the official policy controller has a small maintainer base for a component sitting in a cluster admission path.
- Upgrades break pipelines. Version 3 changed defaults, version 4 is announced as removing legacy functionality and roughly half the command line flags, and two official client libraries still lacked support for the new log format as of mid 2026.
- Signatures do not expire. An artifact signed before a maintainer account was compromised and one signed after are indistinguishable unless somebody is actively monitoring the transparency log, and almost nobody is.
Keil MDK
- Pricing for Essential and Professional subscriptions not disclosed on primary site
- Customers must contact Arm Developer Tools store for subscription rates
Pricing, plan by plan
Cosign
Free- CosignFree
- Apache-2.0
- Public Sigstore infrastructure free to use
- No usage limits published
Keil MDK
FreeNo published plan breakdown. See the Keil MDK review.
Which should you pick?
Choose Cosign if
- You need keyless signing.
- You want to start without paying.
- You work on macOS, Linux, Windows, Docker.
- You also want key and kms signing.
Questions people ask
- Is Cosign or Keil MDK better?
- Neither clearly leads. Cosign starts at Free and Keil MDK at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Cosign or Keil MDK?
- Cosign starts at Free and Keil MDK at Free.
- Does Cosign or Keil MDK run on more platforms?
- Cosign runs on macOS, Linux, Windows, Docker. Keil MDK runs on Web.
- Can I use Cosign for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Cosign best used for?
- Cosign is most often used for signing container images in a build pipeline without managing long-lived private keys, attaching a signed bill of materials to a release so consumers can verify its provenance, meeting a customer or regulatory requirement for signed artifacts, verifying third-party images before they enter an internal registry. Of those, signing container images in a build pipeline without managing long-lived private keys and attaching a signed bill of materials to a release so consumers can verify its provenance are not what Keil MDK is typically brought in for.
- What can Cosign do that Keil MDK cannot?
- Cosign covers Keyless signing, Key and KMS signing, Registry-native storage, In-toto attestations.
Answered from the vendors’ own pages
Cosign: Does Cosign tell me if an image is vulnerable?
No. It has no vulnerability knowledge whatsoever. It can carry an SBOM as a signed attestation but never reads it. Pair it with a scanner.
Keil MDK: Does Keil MDK have a free version?
Yes, Keil MDK Community Edition is free for non-commercial projects. Essential and Professional editions are available as monthly or annual subscriptions.
SourceCosign: Is signing alone enough?
No. Verification is a command somebody runs. Without an admission controller enforcing it, an unsigned image still runs.
Keil MDK: How much do Keil MDK paid editions cost?
Specific pricing for Essential and Professional editions is not published on the main site. Rates are available from the Arm Developer Tools store or by contacting Arm sales.
SourceCosign: What does a bare cosign verify actually prove?
Very little. Without a pinned certificate identity and OIDC issuer, it accepts a valid signature from any identity at all.
Cosign: What is the risk of keyless signing?
Your OIDC provider becomes the root of trust. Compromise of that account yields genuine, verifiable signatures, so account security is the control that matters.
Cosign: Should we expect breaking changes?
Yes. Version 4 is announced to remove roughly half the flags, and a post-quantum migration is named as a further breaking change after that.
Related pages
Other head to heads
- Cosign vs Sigstore
- Cosign vs Syft
- Cosign vs Chainguard
- Cosign vs HashiCorp Vault
- Cosign vs Infisical
- Cosign vs OWASP ZAP
- Cosign vs Wireshark
- Cosign vs Bitwarden
- Cosign vs Semgrep
- Cosign vs Trivy
- Cosign vs authentik
- Cosign vs Microsoft Intune
- Cosign vs Netwrix
- Cosign vs NordVPN
- Cosign vs Omada Identity
- Cosign vs Ory
- Cosign vs ProtonVPN
- Cosign vs Grype
- Cosign vs IAR Embedded Workbench
- Cosign vs CLion
- Cosign vs GNAT Pro
- Cosign vs Rust
- Cosign vs Visual Studio
- Cosign vs Penpot
- Cosign vs Depot
- Cosign vs Ansible
- Cosign vs Helix
- Cosign vs Atlantis
- Cosign vs Jitsu
- Cosign vs StackBlitz
- Cosign vs Pants Build
- Cosign vs Swagger UI
- Cosign vs Yarn
- Cosign vs Buildkite
- Keil MDK vs Sigstore
- Keil MDK vs Syft
- Keil MDK vs Chainguard
- Keil MDK vs HashiCorp Vault
- Keil MDK vs Infisical
- Keil MDK vs OWASP ZAP
- Keil MDK vs Wireshark
- Keil MDK vs Bitwarden
- Keil MDK vs Semgrep
- Keil MDK vs Trivy
- Keil MDK vs authentik
- Keil MDK vs Microsoft Intune
- Keil MDK vs Netwrix
- Keil MDK vs NordVPN
- Keil MDK vs Omada Identity
- Keil MDK vs Ory
- Keil MDK vs ProtonVPN
- Keil MDK vs Grype
- Keil MDK vs IAR Embedded Workbench
- Keil MDK vs CLion
- Keil MDK vs GNAT Pro
- Keil MDK vs Rust
- Keil MDK vs Visual Studio
- Keil MDK vs Penpot
- Keil MDK vs Depot
- Keil MDK vs Ansible
- Keil MDK vs Helix
- Keil MDK vs Atlantis
- Keil MDK vs Jitsu
- Keil MDK vs StackBlitz
- Keil MDK vs Pants Build
- Keil MDK vs Swagger UI
- Keil MDK vs Yarn
- Keil MDK vs Buildkite