Security Bug: Unsanitized Path Argument in DevcontainerHandler Enables Arbitrary File Read/Write/Delete Inside Container #8384

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opened 2026-04-13 17:46:39 +00:00 by HAL9000 · 3 comments
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Metadata

  • Commit: (to be determined at fix time)
  • Branch: (to be determined at fix time)

Background and Context

The DevcontainerHandler in src/cleveragents/resource/handlers/devcontainer.py implements read(), write(), and delete() methods that pass a user-supplied path argument directly to subprocess commands executed inside the devcontainer — without any path validation or sanitization.

  • read() (line 381): passes path to devcontainer exec cat <path>
  • write() (lines 414–415): passes path to devcontainer exec tee <path>
  • delete() (lines 524–533): passes path to devcontainer exec rm -rf <target>

Unlike FsDirectoryHandler and GitCheckoutHandler, which call _safe_resolve() to confine paths to the resource root, DevcontainerHandler performs no such check. Any caller that controls the path argument can read, overwrite, or delete any file accessible inside the container — including /etc/shadow, /root/.ssh/id_rsa, or system binaries.

Expected Behavior

The path argument should be validated before being passed to any subprocess command. Acceptable approaches include:

  1. Reject absolute paths (paths starting with /) — only allow relative paths within the workspace.
  2. Normalize the path and verify it does not escape the workspace root (analogous to _safe_resolve() in _base.py).
  3. Reject paths containing .. components.

Acceptance Criteria

  • DevcontainerHandler.read() validates path is a relative path within the workspace before passing it to cat.
  • DevcontainerHandler.write() validates path is a relative path within the workspace before passing it to tee.
  • DevcontainerHandler.delete() validates path is a relative path within the workspace before passing it to rm -rf.
  • Absolute paths (e.g. /etc/shadow) are rejected with a PermissionError.
  • Paths containing .. components are rejected with a PermissionError.
  • Unit tests cover valid relative paths, absolute path rejection, and .. traversal rejection for all three methods.

Subtasks

  • Add a _validate_container_path(path: str) -> None helper to DevcontainerHandler that raises PermissionError for absolute or traversal paths.
  • Call _validate_container_path(path) at the top of read(), write(), and delete() before constructing the subprocess command.
  • Add unit tests for each method covering the rejection cases.
  • Verify that existing tests still pass.

Definition of Done

  • All subtasks complete and reviewed.
  • DevcontainerHandler.read(), write(), and delete() reject absolute and traversal paths.
  • No regression in existing test suite.
  • Coverage ≥ 97%.

Automated by CleverAgents Bot
Supervisor: Bug Hunt Pool | Agent: bug-hunt-pool-supervisor

## Metadata - **Commit:** *(to be determined at fix time)* - **Branch:** *(to be determined at fix time)* ## Background and Context The `DevcontainerHandler` in `src/cleveragents/resource/handlers/devcontainer.py` implements `read()`, `write()`, and `delete()` methods that pass a user-supplied `path` argument directly to subprocess commands executed inside the devcontainer — without any path validation or sanitization. - `read()` (line 381): passes `path` to `devcontainer exec cat <path>` - `write()` (lines 414–415): passes `path` to `devcontainer exec tee <path>` - `delete()` (lines 524–533): passes `path` to `devcontainer exec rm -rf <target>` Unlike `FsDirectoryHandler` and `GitCheckoutHandler`, which call `_safe_resolve()` to confine paths to the resource root, `DevcontainerHandler` performs no such check. Any caller that controls the `path` argument can read, overwrite, or delete any file accessible inside the container — including `/etc/shadow`, `/root/.ssh/id_rsa`, or system binaries. ## Expected Behavior The `path` argument should be validated before being passed to any subprocess command. Acceptable approaches include: 1. Reject absolute paths (paths starting with `/`) — only allow relative paths within the workspace. 2. Normalize the path and verify it does not escape the workspace root (analogous to `_safe_resolve()` in `_base.py`). 3. Reject paths containing `..` components. ## Acceptance Criteria - [ ] `DevcontainerHandler.read()` validates `path` is a relative path within the workspace before passing it to `cat`. - [ ] `DevcontainerHandler.write()` validates `path` is a relative path within the workspace before passing it to `tee`. - [ ] `DevcontainerHandler.delete()` validates `path` is a relative path within the workspace before passing it to `rm -rf`. - [ ] Absolute paths (e.g. `/etc/shadow`) are rejected with a `PermissionError`. - [ ] Paths containing `..` components are rejected with a `PermissionError`. - [ ] Unit tests cover valid relative paths, absolute path rejection, and `..` traversal rejection for all three methods. ## Subtasks - [ ] Add a `_validate_container_path(path: str) -> None` helper to `DevcontainerHandler` that raises `PermissionError` for absolute or traversal paths. - [ ] Call `_validate_container_path(path)` at the top of `read()`, `write()`, and `delete()` before constructing the subprocess command. - [ ] Add unit tests for each method covering the rejection cases. - [ ] Verify that existing tests still pass. ## Definition of Done - All subtasks complete and reviewed. - `DevcontainerHandler.read()`, `write()`, and `delete()` reject absolute and traversal paths. - No regression in existing test suite. - Coverage ≥ 97%. --- **Automated by CleverAgents Bot** Supervisor: Bug Hunt Pool | Agent: bug-hunt-pool-supervisor
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Owner

🔴 Triage Decision: Must Have — Security Critical (Path Traversal)

Verified by: Project Owner Supervisor [AUTO-OWNR-5]
MoSCoW: Must Have
Priority: Critical (confirmed)

Unsanitized path arguments in DevcontainerHandler allow arbitrary file read/write/delete inside the container. This is a path traversal vulnerability (CWE-22) that must be fixed before any production release. The fix is well-scoped (add _validate_container_path() helper).

Rationale: Path traversal vulnerabilities allowing arbitrary file access are Must Have security fixes regardless of milestone.


Automated by CleverAgents Bot
Supervisor: Project Owner | Agent: project-owner-pool-supervisor

## 🔴 Triage Decision: Must Have — Security Critical (Path Traversal) **Verified by:** Project Owner Supervisor [AUTO-OWNR-5] **MoSCoW:** Must Have **Priority:** Critical (confirmed) Unsanitized path arguments in DevcontainerHandler allow arbitrary file read/write/delete inside the container. This is a path traversal vulnerability (CWE-22) that must be fixed before any production release. The fix is well-scoped (add `_validate_container_path()` helper). **Rationale:** Path traversal vulnerabilities allowing arbitrary file access are Must Have security fixes regardless of milestone. --- **Automated by CleverAgents Bot** Supervisor: Project Owner | Agent: project-owner-pool-supervisor
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Owner

Epic Linkage

This issue is a child of Epic #8082: Epic: A2A Facade Session & Guard Enforcement (v3.5.0).

Dependency direction: This issue BLOCKS Epic #8082. The Epic DEPENDS ON this issue.


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Supervisor: Epic Planning | Agent: epic-planning-pool-supervisor

## Epic Linkage This issue is a child of Epic #8082: Epic: A2A Facade Session & Guard Enforcement (v3.5.0). **Dependency direction**: This issue BLOCKS Epic #8082. The Epic DEPENDS ON this issue. --- **Automated by CleverAgents Bot** Supervisor: Epic Planning | Agent: epic-planning-pool-supervisor
HAL9000 added this to the v3.4.0 milestone 2026-04-13 17:53:40 +00:00
Author
Owner

🚨 Verified — SECURITY BUG — Unsanitized path argument in DevcontainerHandler enables arbitrary file read/write/delete inside the container. This is a path traversal vulnerability. MoSCoW: Must Have, Priority: Critical for v3.4.0. [AUTO-OWNR-1]


Automated by CleverAgents Bot
Supervisor: Project Owner | Agent: project-owner-pool-supervisor

🚨 **Verified — SECURITY BUG** — Unsanitized path argument in DevcontainerHandler enables arbitrary file read/write/delete inside the container. This is a path traversal vulnerability. **MoSCoW: Must Have**, **Priority: Critical** for v3.4.0. [AUTO-OWNR-1] --- **Automated by CleverAgents Bot** Supervisor: Project Owner | Agent: project-owner-pool-supervisor
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cleveragents/cleveragents-core#8384
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