# CVE-2026-55609: sublinear-time-solver: Arbitrary file write in consciousness-explorer / sublinear-time-solver MCP export_state

> An attacker can read, write, or overwrite arbitrary files via path traversal in MCP export/import tools, compromising confidentiality and integrity.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Aug 2026
- **Updated:** 26 Aug 2026
- **Also known as:** GHSA-xc9g-j69q-37xw

## What is CVE-2026-55609?

CVE-2026-55609 is a high-severity path traversal vulnerability in ruvnet sublinear-time-solver, published on 25 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

sublinear-time-solver is a Rust and WebAssembly library for solving asymmetric diagonally dominant systems in sublinear time. Prior to consciousness-explorer 1.1.2 and sublinear-time-solver 1.6.0, the export_state and import_state tools in src/consciousness-explorer/mcp/server.js pass the attacker-controlled filepath parameter to filesystem operations in src/consciousness-explorer/index.js without restricting the destination or rejecting traversal. The saveVectorToFile and loadVectorFromFile tools in src/mcp/server.ts contain the same sink class through the file_path parameter. An attacker able to invoke the MCP tools can read, write, or overwrite any file accessible to the server process, causing confidentiality and integrity loss and possible service disruption. This issue is fixed in consciousness-explorer 1.1.2 and sublinear-time-solver 1.6.0.

Weakness: CWE-73 (External Control of File Name or Path)

## Which versions are affected by CVE-2026-55609?

4 open source packages ship an affected version, including sublinear-time-solver and consciousness-explorer.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `sublinear-time-solver` | npm | All versions | 1.6.0 |
| `sublinear-time-solver` | npm | All versions | 1.6.0 |
| `consciousness-explorer` | npm | All versions | 1.1.2 |
| `consciousness-explorer` | npm | All versions | 1.1.2 |

## How do I fix CVE-2026-55609?

Upgrade sublinear-time-solver to 1.6.0 or later.

## Is CVE-2026-55609 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55609 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55609 and fix it if it is affected.

What it is: CVE-2026-55609 is a high-severity path traversal vulnerability in ruvnet sublinear-time-solver, published on 25 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55609 exists.

Affected packages and fixed versions:
- sublinear-time-solver (npm): affected all versions; fixed in 1.6.0
- sublinear-time-solver (npm): affected all versions; fixed in 1.6.0
- consciousness-explorer (npm): affected all versions; fixed in 1.1.2
- consciousness-explorer (npm): affected all versions; fixed in 1.1.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-55609/ (Markdown: https://insights.sbomify.com/CVE-2026-55609/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55609
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55609
- OSV: https://osv.dev/vulnerability/CVE-2026-55609

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55609/
Summaries are generated and may contain mistakes; the official description above is the record.