Path TraversalWeakness · CWE-22

CVE-2026-29870

HIGH · 7.6 CVSS v3.1 Published 2026-03-31
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
82/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A directory traversal vulnerability in the agentic-context-engine project versions up to 0.7.1 allows arbitrary file writes via the checkpoint_dir parameter in OfflineACE.run. The save_to_file method in ace/skillbook.py fails to normalize or validate filesystem paths, allowing traversal sequences to escape the intended checkpoint directory. This vulnerability allows attackers to overwrite arbitrary files accessible to the application process, potentially leading to application corruption, privilege escalation, or code execution depending on the deployment context.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A directory traversal vulnerability in the agentic-context-engine (versions up to 0.7.1) allows arbitrary file writes via the checkpoint_dir parameter in OfflineACE.run. The save_to_file method in ace/skillbook.py does not normalize or validate filesystem paths, permitting traversal sequences (e.g., ../../../') to escape the intended checkpoint directory and overwrite arbitrary files accessible to the application process.

MitigationImplement strict path validation and normalization in the save_to_file method to ensure all file writes remain within the designated checkpoint directory. Use os.path.realpath() to resolve absolute paths and verify the resolved path starts with the intended checkpoint directory prefix before allowing file operations.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
High
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed version of agentic-context-engine
    Run 'pip show agentic-context-engine' or 'pip list | grep agentic-context-engine' to identify the installed version
    Affected if The installed version is 0.7.1 or lower (including any pre-release versions up to 0.7.1)
  2. Locate the ace/skillbook.py file in the installation
    Run 'python -c "import ace.skillbook; print(ace.skillbook.__file__)"' to find the file path, then inspect the save_to_file method for path validation
    Affected if The save_to_file method lacks os.path.realpath() canonicalization and directory boundary validation before file writes
  3. Identify usage of OfflineACE.run with checkpoint_dir
    Search codebase for 'OfflineACE' and 'checkpoint_dir' usage patterns: grep -r 'OfflineACE' and grep -r 'checkpoint_dir' in project Python files
    Affected if OfflineACE.run is called with a checkpoint_dir parameter that could accept traversal sequences
  4. Audit for files written outside intended checkpoint directory
    Review application logs, filesystem, or compare known checkpoint directory contents against unexpected files in parent directories or sensitive system paths
    Affected if Files exist in locations outside the intended checkpoint_dir that were created by the application process

You are affected if agentic-context-engine version 0.7.1 or lower is installed AND your code uses OfflineACE.run with the checkpoint_dir parameter without additional path validation layers in place.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict path validation and normalization in the save_to_file method to ensure all file writes remain within the designated checkpoint directory. Use os.path.realpath() to resolve absolute paths and verify the resolved path starts with the intended checkpoint directory prefix before allowing file operations.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-29870 in production — separate from our analysis above.

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What this is

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