Arbitrary JSON read and write via traversal
Published Aug 9, 2026 · Updated Aug 9, 2026
Path traversal in angrysky56 advanced-reasoning-mcp 1.0.0 allows local users to read and write arbitrary JSON files. The get_system_json and switch_memory_library handlers append caller-controlled names to storage paths without verifying that the resolved paths remain under memory_data. A connected MCP client can escape the intended storage roots to read JSON files or redirect later memory persistence writes to attacker-chosen JSON paths.
Summary
What happened
Path traversal in angrysky56 advanced-reasoning-mcp 1.0.0 allows local users to read and write arbitrary JSON files. The get_system_json and switch_memory_library handlers append caller-controlled names to storage paths without verifying that the resolved paths remain under memory_data. A connected MCP client can escape the intended storage roots to read JSON files or redirect later memory persistence writes to attacker-chosen JSON paths.
The record
- CVE
- CVE-2026-19330
- Published
- Aug 9, 2026
- Updated
- Aug 9, 2026
- Vendor
- angrysky56
- Product
- advanced-reasoning-mcp
- Classifications
- CWE-22, T1565.001, T1005
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 9, 2026CVE publishedPublication date reported by the CVE source.
- Aug 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.0.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- JSON name traversal proof of conceptproof of concept · unverified
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Technologies
Your stack
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Your stack
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