CVE-2026-9468: Cline MCP Memory Bank Path Traversal Flaw

CVE-2026-9468 Overview

CVE-2026-9468 is a path traversal vulnerability [CWE-22] affecting the dazeb cline-mcp-memory-bank project up to commit 55c81b9cf6c16700983c84dc4cdea3cafa19a75f. The flaw resides in the handleInitializeMemoryBank function within src/index.ts. Attackers can manipulate the projectPath argument to traverse directories outside the intended scope. The exploit is publicly available, increasing the likelihood of opportunistic abuse. Because the project uses a rolling release model, the maintainers do not publish discrete version identifiers for affected or patched builds. The maintainers were notified through a public issue report but had not responded at the time of disclosure.

Critical Impact
Remote authenticated attackers can read or write files outside the intended memory bank directory by supplying crafted projectPath values to handleInitializeMemoryBank.

Affected Products

dazeb cline-mcp-memory-bank up to commit 55c81b9cf6c16700983c84dc4cdea3cafa19a75f
All rolling-release builds prior to a maintainer fix
Deployments exposing the Model Context Protocol (MCP) interface to untrusted callers

Discovery Timeline

2026-05-25 - CVE-2026-9468 published to NVD
2026-05-26 - Last updated in NVD database

Technical Details for CVE-2026-9468

Vulnerability Analysis

The vulnerability is a classic path traversal weakness in the handleInitializeMemoryBank function of src/index.ts. This function accepts a projectPath argument from the caller and uses it when initializing a memory bank directory on disk. The implementation does not normalize or restrict the supplied path to a safe base directory. As a result, sequences such as ../ allow the attacker to direct file operations to arbitrary locations on the host filesystem.

The project is an MCP (Model Context Protocol) memory bank used by Cline-based AI assistants. When invoked remotely, the handler runs with the privileges of the MCP server process. Successful exploitation can lead to unauthorized file creation, overwriting of configuration files, or disclosure of sensitive content within reach of the server account.

Root Cause

The root cause is missing input validation on the projectPath parameter. The handler does not canonicalize the path with a function such as path.resolve followed by a containment check against an allow-listed root. Without that boundary check, attacker-controlled traversal segments are passed directly to filesystem APIs.

Attack Vector

Exploitation occurs over the network against an exposed MCP endpoint. An attacker with low privileges sends an initialization request containing a projectPath value that escapes the intended directory, for example by prefixing the value with multiple ../ segments or supplying an absolute path. No user interaction is required.

No verified proof-of-concept code is published in a structured advisory. See the GitHub Issue Discussion and the GitHub Repository for technical context.

Detection Methods for CVE-2026-9468

Indicators of Compromise

Requests to the MCP initializeMemoryBank handler containing ../, ..\, or absolute paths in the projectPath field
Unexpected directories or memory-bank artifacts created outside the configured workspace root
Modifications to sensitive files such as .env, .ssh/authorized_keys, or application configuration files by the MCP server process

Detection Strategies

Inspect MCP server logs for handleInitializeMemoryBank invocations and flag any projectPath value containing traversal sequences or absolute prefixes
Apply filesystem auditing (auditd on Linux, Sysmon FileCreate events on Windows) to the MCP service account, alerting on writes outside the expected project root
Compare canonicalized projectPath values against an allow-listed base directory and alert on mismatches

Monitoring Recommendations

Forward MCP server logs and filesystem audit events to a centralized analytics platform for correlation and retention
Track process lineage of the MCP server to detect downstream execution of files written through the traversal
Establish a baseline of legitimate projectPath values and alert on outliers

How to Mitigate CVE-2026-9468

Immediate Actions Required

Restrict network exposure of the MCP server to trusted local callers until a fix is available
Run the MCP server under a least-privileged account that cannot reach sensitive directories
Apply a local patch that validates projectPath against an allow-listed root before any filesystem operation

Patch Information

No official patch has been released. The maintainers were notified through the GitHub Issue Discussion but had not responded at the time of CVE publication. Track the GitHub Repository and the VulDB Entry for status updates.

Workarounds

Wrap handleInitializeMemoryBank with a validation layer that calls path.resolve(base, projectPath) and rejects any result that does not start with the configured base directory
Reject projectPath values containing .., null bytes, or absolute path prefixes before invoking the handler
Place the MCP server inside a container or chroot with read-only access to everything outside the intended workspace
Disable the memory bank initialization feature if it is not required in your deployment

bash

# Configuration example - sample validation logic to apply before invoking the handler
# Pseudocode for a wrapper around handleInitializeMemoryBank
# const base = path.resolve('/srv/mcp/workspaces');
# const target = path.resolve(base, projectPath);
# if (!target.startsWith(base + path.sep)) {
#   throw new Error('Invalid projectPath: traversal attempt blocked');
# }