diff --git a/src/shell/builtin/seq.zig b/src/shell/builtin/seq.zig
index f5b0061fa7..ab29d821ee 100644
--- a/src/shell/builtin/seq.zig
+++ b/src/shell/builtin/seq.zig
@@ -46,12 +46,14 @@ pub fn start(this: *@This()) Yield {
 
     const maybe1 = iter.next().?;
     const int1 = std.fmt.parseFloat(f32, bun.sliceTo(maybe1, 0)) catch return this.fail("seq: invalid argument\n");
+    if (!std.math.isFinite(int1)) return this.fail("seq: invalid argument\n");
     this._end = int1;
     if (this._start > this._end) this.increment = -1;
 
     const maybe2 = iter.next();
     if (maybe2 == null) return this.do();
     const int2 = std.fmt.parseFloat(f32, bun.sliceTo(maybe2.?, 0)) catch return this.fail("seq: invalid argument\n");
+    if (!std.math.isFinite(int2)) return this.fail("seq: invalid argument\n");
     this._start = int1;
     this._end = int2;
     if (this._start < this._end) this.increment = 1;
@@ -60,6 +62,7 @@ pub fn start(this: *@This()) Yield {
     const maybe3 = iter.next();
     if (maybe3 == null) return this.do();
     const int3 = std.fmt.parseFloat(f32, bun.sliceTo(maybe3.?, 0)) catch return this.fail("seq: invalid argument\n");
+    if (!std.math.isFinite(int3)) return this.fail("seq: invalid argument\n");
     this._start = int1;
     this.increment = int2;
     this._end = int3;
diff --git a/src/shell/states/CondExpr.zig b/src/shell/states/CondExpr.zig
index 75c1dd2f37..9bec738fdd 100644
--- a/src/shell/states/CondExpr.zig
+++ b/src/shell/states/CondExpr.zig
@@ -168,6 +168,8 @@ fn commandImplStart(this: *CondExpr) Yield {
         .@"-d",
         .@"-f",
         => {
+            // Empty string expansion produces no args; the path doesn't exist.
+            if (this.args.items.len == 0) return this.parent.childDone(this, 1);
             this.state = .waiting_stat;
             return this.doStat();
         },
diff --git a/test/js/bun/shell/shell-seq-condexpr.test.ts b/test/js/bun/shell/shell-seq-condexpr.test.ts
new file mode 100644
index 0000000000..adb1756d92
--- /dev/null
+++ b/test/js/bun/shell/shell-seq-condexpr.test.ts
@@ -0,0 +1,85 @@
+import { expect, test } from "bun:test";
+import { bunEnv, bunExe } from "harness";
+
+test("seq inf does not hang", async () => {
+  await using proc = Bun.spawn({
+    cmd: [
+      bunExe(),
+      "-e",
+      `import { $ } from "bun"; $.throws(false); const r = await $\`seq inf\`; process.exit(r.exitCode)`,
+    ],
+    env: bunEnv,
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toContain("invalid argument");
+  expect(exitCode).toBe(1);
+}, 10_000);
+
+test("seq nan does not hang", async () => {
+  await using proc = Bun.spawn({
+    cmd: [
+      bunExe(),
+      "-e",
+      `import { $ } from "bun"; $.throws(false); const r = await $\`seq nan\`; process.exit(r.exitCode)`,
+    ],
+    env: bunEnv,
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toContain("invalid argument");
+  expect(exitCode).toBe(1);
+}, 10_000);
+
+test("seq -inf does not hang", async () => {
+  await using proc = Bun.spawn({
+    cmd: [
+      bunExe(),
+      "-e",
+      `import { $ } from "bun"; $.throws(false); const r = await $\`seq -- -inf\`; process.exit(r.exitCode)`,
+    ],
+    env: bunEnv,
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toContain("invalid argument");
+  expect(exitCode).toBe(1);
+}, 10_000);
+
+test('[[ -d "" ]] does not crash', async () => {
+  await using proc = Bun.spawn({
+    cmd: [
+      bunExe(),
+      "-e",
+      `import { $ } from "bun"; $.throws(false); const r = await $\`[[ -d "" ]]\`; process.exit(r.exitCode)`,
+    ],
+    env: bunEnv,
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(exitCode).toBe(1);
+}, 10_000);
+
+test('[[ -f "" ]] does not crash', async () => {
+  await using proc = Bun.spawn({
+    cmd: [
+      bunExe(),
+      "-e",
+      `import { $ } from "bun"; $.throws(false); const r = await $\`[[ -f "" ]]\`; process.exit(r.exitCode)`,
+    ],
+    env: bunEnv,
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(exitCode).toBe(1);
+}, 10_000);