GHSA-2m67-cxxq-c3h8
ZeptoClaw: Path boundary checks bypass via symlink, TOCTOU, and hardlink
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
zeptoclawReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Workspace boundary enforcement currently has three related bypass risks. This issue tracks fixing all three in one pull request.
Details
R1 - Dangling Symlink Component Bypass
- What happens: Path validation can miss dangling symlink components during traversal checks.
- Why it matters: A symlink that is unresolved at validation time can later resolve to an external location.
- Impact: Read and write operations may escape workspace boundaries.
- Affected area: src/security/path.rs (check_symlink_escape).
R2 - TOCTOU Between Validation and Use
- What happens: The path is validated first, then used later for filesystem operations.
- Why it matters: A concurrent filesystem change can swap path components after validation but before open/write.
- Impact: Race-based workspace escape is possible.
- Affected area: Filesystem and file-consuming tools that call validate_path_in_workspace before I/O.
R3 - Hardlink Alias Bypass
- What happens: A file inside workspace can be a hardlink to an inode outside the intended workspace trust boundary.
- Why it matters: Prefix and symlink checks can pass while data access still mutates or reads external content.
- Impact: Policy bypass for read/write operations.
- Affected area: Any tool that reads or writes via validated paths.
Risk Matrix
| ID | Risk | Severity | Likelihood | Impact |
|---|---|---|---|---|
| R1 | Dangling symlink component bypass | High | Medium | Workspace boundary escape for read/write |
| R2 | Validate/use TOCTOU race | High | Medium | Race-based boundary escape during file I/O |
| R3 | Hardlink alias bypass | Medium | Low-Medium | External inode read/write through in-workspace path |
PoC
R1 - Dangling symlink component bypass
- Create a symlink inside workspace pointing to a missing target.
- Validate a path traversing that symlink.
- Create the target directory outside workspace after validation.
- Perform file operation and observe potential boundary escape if not fail-closed.
R2 - TOCTOU between validation and use
- Validate a candidate in-workspace path.
- Before open/write, replace an intermediate component with a link to external location.
- Continue with the file operation.
- Observe boundary escape if operation trusts only stale validation result.
R3 - Hardlink alias bypass
- Place a hardlink inside workspace that points to an external inode.
- Validate the in-workspace hardlink path.
- Read or write through this path.
- Observe external inode access through a path that appears in-scope.
Impacts
Unauthorized cross path boundary
Credit
Patch
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | zeptoclaw | all versions | 0.7.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zeptoclaw. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update zeptoclaw to 0.7.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2m67-cxxq-c3h8 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-2m67-cxxq-c3h8 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-2m67-cxxq-c3h8. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-2m67-cxxq-c3h8 in your dependencies?
O3 detects GHSA-2m67-cxxq-c3h8 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.