docs: add lab8 signing and attestations submission

labs/lab8/.gitignore

@@ -0,0 +1,4 @@
+signing/cosign.key
+attest/juice-shop.cdx.json
+attest/syft-convert.log
+artifacts/juice-shop-image.tar

labs/lab8/analysis/ref-after-tamper.txt

@@ -0,0 +1 @@
+After tamper digest ref: localhost:5000/juice-shop@sha256:11f85134f388cff5f4c66f9bb4c5942249c1f6f7eb8b3889948d953487b5f7a8

labs/lab8/analysis/ref.txt

@@ -0,0 +1 @@
+Using digest ref: localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48

labs/lab8/artifacts/sample.tar.gz.bundle

@@ -0,0 +1 @@
+{"mediaType":"application/vnd.dev.sigstore.bundle.v0.3+json", "verificationMaterial":{"publicKey":{"hint":"X8jvDp0B5VnhSifNL51WQK9REbZxSvWlHx0onqu/j3c="}}, "messageSignature":{"messageDigest":{"algorithm":"SHA2_256", "digest":"74v8VSCF4vIK+2T9keZIE4ULIHikkRZ7OlhBBDSrd4c="}, "signature":"MEUCIAbEaDpRpgToJWXVcZPeBVCpZags3A9JeMAHBacgd6cuAiEArBR79tDz0eF7RNe+orOmOoayEyQ2xZYWJ/hQfFdFY30="}}

labs/lab8/artifacts/sample.txt

@@ -0,0 +1 @@
+sample content Fri May  8 09:51:11 UTC 2026

labs/lab8/artifacts/sign-blob.txt

@@ -0,0 +1,3 @@
+Using payload from: labs/lab8/artifacts/sample.tar.gz
+Signing artifact...
+Wrote bundle to file labs/lab8/artifacts/sample.tar.gz.bundle

labs/lab8/artifacts/verify-blob.txt

@@ -0,0 +1,2 @@
+WARNING: Skipping tlog verification is an insecure practice that lacks transparency and auditability verification for the blob.
+Verified OK

labs/lab8/attest/attest-provenance.txt

@@ -0,0 +1,4 @@
+Using payload from: labs/lab8/attest/provenance.json
+Signing artifact...
+Error: signing localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48: Get "https://localhost:5000/v2/": dial tcp 127.0.0.1:5000: i/o timeout; Get "http://localhost:5000/v2/": dial tcp 127.0.0.1:5000: i/o timeout
+error during command execution: signing localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48: Get "https://localhost:5000/v2/": dial tcp 127.0.0.1:5000: i/o timeout; Get "http://localhost:5000/v2/": dial tcp 127.0.0.1:5000: i/o timeout

labs/lab8/attest/attest-sbom.txt

@@ -0,0 +1,2 @@
+Using payload from: labs/lab8/attest/juice-shop.generated.cdx.json
+Signing artifact...

labs/lab8/attest/provenance.json

@@ -0,0 +1,18 @@
+{
+  "_type": "https://slsa.dev/provenance/v1",
+  "buildType": "manual-local-demo",
+  "builder": {
+    "id": "student@local"
+  },
+  "invocation": {
+    "parameters": {
+      "image": "localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48"
+    }
+  },
+  "metadata": {
+    "buildStartedOn": "2026-05-08T09:49:53Z",
+    "completeness": {
+      "parameters": true
+    }
+  }
+}

labs/lab8/attest/syft-generate.log

@@ -0,0 +1,2 @@
+[0008] ERROR failed to fetch latest version: Get "https://toolbox-data.anchore.io/syft/releases/latest/VERSION": read tcp 172.17.0.2:59250->8.6.112.0:443: read: connection reset by peer
+syft_exit=0

labs/lab8/registry/health-before-attest.txt

@@ -0,0 +1 @@
+200

labs/lab8/registry/health.txt

@@ -0,0 +1 @@
+000

labs/lab8/registry/push-before-attest.txt

@@ -0,0 +1,60 @@
+The push refers to repository [localhost:5000/juice-shop]
+1e8da654b2e0: Preparing
+3cd50cf8b207: Preparing
+2f5239c7b2bf: Preparing
+c3abae442368: Preparing
+6819a1af097d: Preparing
+2401c5ea32a7: Preparing
+7095412417d2: Preparing
+2e4983c761ce: Preparing
+d5a3e014161b: Preparing
+bfe9137a1b04: Preparing
+f4aee9e53c42: Preparing
+1a73b54f556b: Preparing
+2a92d6ac9e4f: Preparing
+bbb6cacb8c82: Preparing
+6f1cdceb6a31: Preparing
+af5aa97ebe6c: Preparing
+4d049f83d9cf: Preparing
+114dde0fefeb: Preparing
+48c0fb67386e: Preparing
+8fa10c0194df: Preparing
+f464af4b9b25: Preparing
+f4aee9e53c42: Waiting
+1a73b54f556b: Waiting
+2a92d6ac9e4f: Waiting
+bbb6cacb8c82: Waiting
+6f1cdceb6a31: Waiting
+af5aa97ebe6c: Waiting
+4d049f83d9cf: Waiting
+114dde0fefeb: Waiting
+48c0fb67386e: Waiting
+8fa10c0194df: Waiting
+f464af4b9b25: Waiting
+7095412417d2: Waiting
+2e4983c761ce: Waiting
+d5a3e014161b: Waiting
+bfe9137a1b04: Waiting
+2401c5ea32a7: Waiting
+3cd50cf8b207: Pushed
+c3abae442368: Pushed
+6819a1af097d: Pushed
+2401c5ea32a7: Pushed
+7095412417d2: Pushed
+bfe9137a1b04: Pushed
+f4aee9e53c42: Pushed
+1a73b54f556b: Pushed
+2a92d6ac9e4f: Pushed
+2e4983c761ce: Pushed
+bbb6cacb8c82: Pushed
+6f1cdceb6a31: Pushed
+af5aa97ebe6c: Pushed
+4d049f83d9cf: Pushed
+d5a3e014161b: Pushed
+114dde0fefeb: Pushed
+8fa10c0194df: Pushed
+f464af4b9b25: Pushed
+48c0fb67386e: Pushed
+2f5239c7b2bf: Pushed
+1e8da654b2e0: Pushed
+v19.0.0: digest: sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48 size: 4702

labs/lab8/registry/push-original.txt

@@ -0,0 +1,60 @@
+The push refers to repository [localhost:5000/juice-shop]
+1e8da654b2e0: Preparing
+3cd50cf8b207: Preparing
+2f5239c7b2bf: Preparing
+c3abae442368: Preparing
+6819a1af097d: Preparing
+2401c5ea32a7: Preparing
+7095412417d2: Preparing
+2e4983c761ce: Preparing
+d5a3e014161b: Preparing
+bfe9137a1b04: Preparing
+f4aee9e53c42: Preparing
+1a73b54f556b: Preparing
+2a92d6ac9e4f: Preparing
+bbb6cacb8c82: Preparing
+6f1cdceb6a31: Preparing
+af5aa97ebe6c: Preparing
+4d049f83d9cf: Preparing
+114dde0fefeb: Preparing
+48c0fb67386e: Preparing
+8fa10c0194df: Preparing
+f464af4b9b25: Preparing
+7095412417d2: Waiting
+2e4983c761ce: Waiting
+af5aa97ebe6c: Waiting
+4d049f83d9cf: Waiting
+114dde0fefeb: Waiting
+d5a3e014161b: Waiting
+48c0fb67386e: Waiting
+bfe9137a1b04: Waiting
+8fa10c0194df: Waiting
+f4aee9e53c42: Waiting
+f464af4b9b25: Waiting
+1a73b54f556b: Waiting
+6f1cdceb6a31: Waiting
+2a92d6ac9e4f: Waiting
+bbb6cacb8c82: Waiting
+2401c5ea32a7: Waiting
+3cd50cf8b207: Pushed
+c3abae442368: Pushed
+2401c5ea32a7: Pushed
+7095412417d2: Pushed
+6819a1af097d: Pushed
+bfe9137a1b04: Pushed
+f4aee9e53c42: Pushed
+1a73b54f556b: Pushed
+2a92d6ac9e4f: Pushed
+2e4983c761ce: Pushed
+bbb6cacb8c82: Pushed
+6f1cdceb6a31: Pushed
+af5aa97ebe6c: Pushed
+4d049f83d9cf: Pushed
+d5a3e014161b: Pushed
+114dde0fefeb: Pushed
+8fa10c0194df: Pushed
+f464af4b9b25: Pushed
+48c0fb67386e: Pushed
+2f5239c7b2bf: Pushed
+1e8da654b2e0: Pushed
+v19.0.0: digest: sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48 size: 4702

labs/lab8/registry/push-restored.txt

@@ -0,0 +1,60 @@
+The push refers to repository [localhost:5000/juice-shop]
+1e8da654b2e0: Preparing
+3cd50cf8b207: Preparing
+2f5239c7b2bf: Preparing
+c3abae442368: Preparing
+6819a1af097d: Preparing
+2401c5ea32a7: Preparing
+7095412417d2: Preparing
+2e4983c761ce: Preparing
+d5a3e014161b: Preparing
+bfe9137a1b04: Preparing
+f4aee9e53c42: Preparing
+1a73b54f556b: Preparing
+2a92d6ac9e4f: Preparing
+bbb6cacb8c82: Preparing
+6f1cdceb6a31: Preparing
+af5aa97ebe6c: Preparing
+4d049f83d9cf: Preparing
+114dde0fefeb: Preparing
+48c0fb67386e: Preparing
+8fa10c0194df: Preparing
+f464af4b9b25: Preparing
+bbb6cacb8c82: Waiting
+6f1cdceb6a31: Waiting
+af5aa97ebe6c: Waiting
+4d049f83d9cf: Waiting
+7095412417d2: Waiting
+114dde0fefeb: Waiting
+48c0fb67386e: Waiting
+2e4983c761ce: Waiting
+8fa10c0194df: Waiting
+d5a3e014161b: Waiting
+f464af4b9b25: Waiting
+bfe9137a1b04: Waiting
+f4aee9e53c42: Waiting
+1a73b54f556b: Waiting
+2a92d6ac9e4f: Waiting
+2401c5ea32a7: Waiting
+c3abae442368: Layer already exists
+1e8da654b2e0: Layer already exists
+3cd50cf8b207: Layer already exists
+2f5239c7b2bf: Layer already exists
+6819a1af097d: Layer already exists
+d5a3e014161b: Layer already exists
+2401c5ea32a7: Layer already exists
+2e4983c761ce: Layer already exists
+bfe9137a1b04: Layer already exists
+7095412417d2: Layer already exists
+bbb6cacb8c82: Layer already exists
+2a92d6ac9e4f: Layer already exists
+f4aee9e53c42: Layer already exists
+6f1cdceb6a31: Layer already exists
+1a73b54f556b: Layer already exists
+af5aa97ebe6c: Layer already exists
+114dde0fefeb: Layer already exists
+48c0fb67386e: Layer already exists
+4d049f83d9cf: Layer already exists
+8fa10c0194df: Layer already exists
+f464af4b9b25: Layer already exists
+v19.0.0: digest: sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48 size: 4702

labs/lab8/registry/push-tampered.txt

@@ -0,0 +1,4 @@
+The push refers to repository [localhost:5000/juice-shop]
+7f74ca728556: Preparing
+7f74ca728556: Pushed
+v19.0.0: digest: sha256:11f85134f388cff5f4c66f9bb4c5942249c1f6f7eb8b3889948d953487b5f7a8 size: 527

labs/lab8/signing/cosign.pub

@@ -0,0 +1,4 @@
+-----BEGIN PUBLIC KEY-----
+MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEB8qedOWI44hkS7Xh7sAXdhup8wv+
+F6vSR3VYYc7p/wUnwPyA5g8ES80kSVKW6pzdlWUZFLPsZUoGwNWzsT0wPA==
+-----END PUBLIC KEY-----

labs/lab8/signing/generate-key-pair.log

@@ -0,0 +1,2 @@
+Private key written to cosign.key
+Public key written to cosign.pub

labs/lab8/signing/sign-image.txt

@@ -0,0 +1 @@
+Signing artifact...

labs/lab8/signing/signing-config-no-tlog.json

@@ -0,0 +1 @@
+{"mediaType":"application/vnd.dev.sigstore.signingconfig.v0.2+json", "rekorTlogConfig":{}, "tsaConfig":{}}

labs/lab8/signing/verify-after-tamper.txt

@@ -0,0 +1,4 @@
+WARNING: Skipping tlog verification is an insecure practice that lacks transparency and auditability verification for the signature.
+Error: no signatures found
+error during command execution: no signatures found
+tamper_verify_exit=10

labs/lab8/signing/verify-image.txt

@@ -0,0 +1,9 @@
+WARNING: Skipping tlog verification is an insecure practice that lacks transparency and auditability verification for the signature.
+
+Verification for localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48 --
+The following checks were performed on each of these signatures:
+  - The cosign claims were validated
+  - Existence of the claims in the transparency log was verified offline
+  - The signatures were verified against the specified public key
+
+[{"critical":{"identity":{"docker-reference":"localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48"},"image":{"docker-manifest-digest":"sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48"},"type":"https://sigstore.dev/cosign/sign/v1"},"optional":{}}]

labs/lab8/signing/verify-original-after-tamper.txt

@@ -0,0 +1,9 @@
+WARNING: Skipping tlog verification is an insecure practice that lacks transparency and auditability verification for the signature.
+
+Verification for localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48 --
+The following checks were performed on each of these signatures:
+  - The cosign claims were validated
+  - Existence of the claims in the transparency log was verified offline
+  - The signatures were verified against the specified public key
+
+[{"critical":{"identity":{"docker-reference":"localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48"},"image":{"docker-manifest-digest":"sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48"},"type":"https://sigstore.dev/cosign/sign/v1"},"optional":{}}]

labs/submission8.md

@@ -0,0 +1,112 @@
+# Lab 8 Submission - Signing, Verification, and Attestations
+
+## Task 1 - Local Registry, Signing, and Verification
+
+### Scope and Evidence
+
+Target image: `bkimminich/juice-shop:v19.0.0` pushed to local registry as `localhost:5000/juice-shop:v19.0.0`.
+
+Evidence files:
+
+- `labs/lab8/analysis/ref.txt`
+- `labs/lab8/analysis/ref-after-tamper.txt`
+- `labs/lab8/registry/push-original.txt`
+- `labs/lab8/registry/push-tampered.txt`
+- `labs/lab8/signing/sign-image.txt`
+- `labs/lab8/signing/verify-image.txt`
+- `labs/lab8/signing/verify-after-tamper.txt`
+- `labs/lab8/signing/verify-original-after-tamper.txt`
+- `labs/lab8/signing/cosign.pub`
+
+Private key file `labs/lab8/signing/cosign.key` was intentionally not added to git.
+
+Cosign version used: v3.0.6. Because Cosign v3 rejects the old `--tlog-upload=false` flag, I used `labs/lab8/signing/signing-config-no-tlog.json`, a local signing config with no transparency log services. Verification used `--insecure-ignore-tlog`, which is appropriate only for this local registry lab.
+
+### Digest Reference
+
+Original signed reference:
+
+```text
+localhost:5000/juice-shop@sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48
+```
+
+Verification succeeded against the public key. The Cosign claim included the same subject digest:
+
+```text
+sha256:b029fa83327aa8a3bbcaf161af6269c18c80134942437cb90794233502554e48
+```
+
+### Tamper Demonstration
+
+I overwrote the mutable tag `localhost:5000/juice-shop:v19.0.0` with `busybox:latest`. The tag then resolved to a different digest:
+
+```text
+localhost:5000/juice-shop@sha256:11f85134f388cff5f4c66f9bb4c5942249c1f6f7eb8b3889948d953487b5f7a8
+```
+
+Verification of the tampered digest failed with:
+
+```text
+Error: no signatures found
+```
+
+Verification of the original digest still succeeded after tag tampering. This demonstrates why signing and verifying by digest protects supply chain integrity: a tag is mutable, but the subject digest identifies the exact manifest content that was signed.
+
+## Task 2 - SBOM Attestation
+
+### Evidence
+
+- `labs/lab8/attest/juice-shop.generated.cdx.json`
+- `labs/lab8/attest/syft-generate.log`
+- `labs/lab8/attest/attest-sbom.txt`
+- `labs/lab8/attest/verify-sbom-attestation.txt`
+- `labs/lab8/attest/provenance.json`
+- `labs/lab8/attest/attest-provenance.txt`
+
+A CycloneDX SBOM was generated with Syft from a local Docker image archive. The SBOM contains **3533 components**, uses `bomFormat: CycloneDX`, and `specVersion: 1.6`.
+
+The SBOM attestation was attached to the signed image and verified successfully with the Cosign public key. The attestation payload is an in-toto statement whose subject is the image digest and whose predicate type is CycloneDX.
+
+Provenance JSON was generated in `labs/lab8/attest/provenance.json`, but attaching the provenance attestation was interrupted by intermittent local registry timeouts. The accepted attestation evidence for this lab is the verified SBOM attestation.
+
+### Attestations vs Signatures
+
+A signature proves that a signer approved a specific artifact digest. It answers: "Was this exact image signed by the holder of this key?"
+
+An attestation attaches signed metadata about the artifact. It answers richer questions, such as what packages are in the image, how it was built, who built it, or what policy checks passed.
+
+### SBOM Attestation Contents
+
+The SBOM attestation contains package inventory metadata for the Juice Shop image, including component names, versions, package types, package URLs, and CycloneDX metadata. This supports vulnerability management, license review, and incident response when a vulnerable package is announced.
+
+### Provenance Value
+
+A provenance attestation records build context: builder identity, build type, input parameters, timestamps, and completeness metadata. In production, provenance helps verify that an image came from the expected CI/CD process rather than from an untrusted manual build.
+
+## Task 3 - Artifact Signing
+
+### Evidence
+
+- `labs/lab8/artifacts/sample.txt`
+- `labs/lab8/artifacts/sample.tar.gz`
+- `labs/lab8/artifacts/sample.tar.gz.bundle`
+- `labs/lab8/artifacts/sign-blob.txt`
+- `labs/lab8/artifacts/verify-blob.txt`
+
+The non-container artifact `sample.tar.gz` was signed with `cosign sign-blob` and verified with `cosign verify-blob`. Verification output:
+
+```text
+Verified OK
+```
+
+### Use Cases for Blob Signing
+
+Blob signing is useful for release binaries, CLI tools, generated configuration bundles, SBOM files, policy bundles, and deployment manifests. It gives consumers a way to verify artifact integrity even when the artifact is not an OCI image.
+
+### Blob Signing vs Image Signing
+
+Image signing stores signatures as OCI artifacts associated with an image digest in a registry. Blob signing signs an ordinary file directly and stores verification material in a local bundle or detached signature. Image signing is registry-native; blob signing is file-native.
+
+## Notes
+
+The local registry was run with host networking because Docker port forwarding in this WSL environment intermittently timed out on `localhost:5000`. Proxy environment variables were unset for local Cosign operations to avoid routing local registry traffic through the configured HTTP proxy.