CVE-2026-50158 yutu: Arbitrary File Write via MCP `caption-download` Tool
Attackers can write arbitrary files via the caption-download tool, potentially overwriting critical files to achieve code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-50158?
CVE-2026-50158 is a high-severity path traversal vulnerability in eat-pray-ai yutu, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
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.
Weakness: CWE-73
Which versions are affected by CVE-2026-50158?
3 open source packages ship an affected version, including github.com/eat-pray-ai/yutu.
| Package | Affected | Fixed in |
|---|---|---|
github.com/eat-pray-ai/yutu Go | All versions | 0.10.9-dev1 |
github.com/eat-pray-ai/yutu Go | All versions | 0.10.9-dev1 |
github.com/eat-pray-ai/yutu Go | All versions | 0.10.9-dev1 |
How do I fix CVE-2026-50158?
Upgrade github.com/eat-pray-ai/yutu to 0.10.9-dev1 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-50158 being exploited?
There is no known exploitation of CVE-2026-50158 in the wild and no public exploit code.
Sources
Also known as GHSA-2c7f-fxww-6w6c, GO-2026-5980.