Vulnerability · Published Sep 17, 2026 · Assigned by GitHub_M

CVE-2026-50158yutu: Arbitrary File Write via MCP `caption-download` Tool

High 7.7

In plain English

A high-severity security flaw in yutu from eat-pray-ai. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.7High
Exploit odds (30 days)0.2%top 86.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

yutu is an AI-powered toolkit for managing and growing YouTube channels. Prior to 0.10.9, the caption-download MCP tool accepts a caller-controlled file parameter through cmd/caption/download.go and passes it to Caption.Download() in pkg/caption/caption.go, where os.Create() creates or truncates that path without using the pkg.Root confinement boundary backed by YUTU_ROOT. A principal able to invoke caption-download, including a local HTTP client when the MCP server runs with its default authentication-disabled configuration, can write downloaded caption bytes to any path writable by the yutu process outside YUTU_ROOT. This can overwrite application files, configuration, shell startup files, logs, or data and can cause persistent code execution or denial of service depending on the selected writable target. Live caption retrieval also requires usable service credentials and an accessible caption identifier. This issue is fixed in version 0.10.9.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/eat-pray-ai/yutu0.10.9-dev1GHSA-2c7f-fxww-6w6c
Gogithub.com/eat-pray-ai/yutu0.10.9-dev1GO-2026-5980

Affected products (as reported)

VendorProductVersions
eat-pray-ai yutu < 0.10.9-dev1

Weakness: CWE-73 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

References