diff --git a/review-enrichment/src/analyzers/actions-pin.ts b/review-enrichment/src/analyzers/actions-pin.ts
index 6aa9fdbe79..1b4e029689 100644
--- a/review-enrichment/src/analyzers/actions-pin.ts
+++ b/review-enrichment/src/analyzers/actions-pin.ts
@@ -5,7 +5,7 @@
 import type { EnrichRequest, ActionPinFinding } from "../types.js";
 
 const USES_RE = /^\s*-?\s*["']?uses["']?\s*:\s*["']?([\w.-]+\/[\w./-]+)@([^\s"'#]+)/;
-const FULL_SHA = /^[0-9a-f]{40}$/;
+const FULL_SHA = /^[0-9a-f]{40}$/i;
 const OFFICIAL = /^(actions|github)\//;
 const WORKFLOW_PATH = /^\.github\/workflows\/.+\.ya?ml$/;
 
diff --git a/review-enrichment/test/actions-pin.test.ts b/review-enrichment/test/actions-pin.test.ts
new file mode 100644
index 0000000000..08ff1c0603
--- /dev/null
+++ b/review-enrichment/test/actions-pin.test.ts
@@ -0,0 +1,45 @@
+// Units for the unpinned GitHub Actions analyzer (#1500). Own file so concurrent analyzer PRs don't collide.
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { scanActionPins, scanWorkflowPins } from "../dist/analyzers/actions-pin.js";
+
+const workflowPatch = (action, ref) =>
+  `@@ -1,2 +1,3 @@\n jobs:\n   test:\n+      - uses: ${action}@${ref}\n`;
+
+test("scanWorkflowPins: accepts uppercase 40-char SHA pins", () => {
+  const sha = "A".repeat(40);
+  assert.deepEqual(
+    scanWorkflowPins(".github/workflows/ci.yml", workflowPatch("tj-actions/changed-files", sha)),
+    [],
+  );
+});
+
+test("scanWorkflowPins: flags mutable third-party refs that are not full SHAs", () => {
+  const findings = scanWorkflowPins(
+    ".github/workflows/ci.yml",
+    workflowPatch("tj-actions/changed-files", "v35"),
+  );
+  assert.equal(findings.length, 1);
+  assert.equal(findings[0]!.action, "tj-actions/changed-files");
+  assert.equal(findings[0]!.ref, "v35");
+});
+
+test("scanWorkflowPins: skips official actions even when unpinned", () => {
+  assert.deepEqual(
+    scanWorkflowPins(".github/workflows/ci.yml", workflowPatch("actions/setup-node", "v4")),
+    [],
+  );
+});
+
+test("scanActionPins: scans changed workflow files only", async () => {
+  const sha = "B".repeat(40);
+  const out = await scanActionPins({
+    repoFullName: "o/r",
+    prNumber: 1,
+    files: [
+      { path: ".github/workflows/ci.yml", patch: workflowPatch("tj-actions/changed-files", sha) },
+      { path: "src/a.ts", patch: workflowPatch("tj-actions/changed-files", "main") },
+    ],
+  });
+  assert.deepEqual(out, []);
+});