marcopiovanello yt-dlp-web-ui up to 4.0.0 JSON-RPC Method /rpc/http Service.Formats argument injection

Summaryinfo

A vulnerability was found in marcopiovanello yt-dlp-web-ui up to 4.0.0. It has been rated as critical. Impacted is the function Service.Formats of the file /rpc/http of the component JSON-RPC Method. This manipulation causes argument injection. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is tracked as CVE-2026-109966. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in marcopiovanello yt-dlp-web-ui up to 4.0.0. It has been declared as critical. Affected by this vulnerability is the function Service.Formats of the file /rpc/http of the component JSON-RPC Method. The manipulation with an unknown input leads to a argument injection vulnerability. The CWE definition for the vulnerability is CWE-88. The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

yt-dlp-web-ui through 4.0.0 contains an argument injection vulnerability that allows unauthenticated remote attackers to inject yt-dlp options by supplying a dash-prefixed url parameter to the Service.Formats JSON-RPC method. Attackers can send values like --load-info-json via /rpc/http or /rpc/ws to make yt-dlp load attacker-chosen JSON files from the server filesystem, with contents reflected in responses.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-109966 since 10/13/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/13/2026). MITRE ATT&CK project uses the attack technique T1059 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-98692). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Data Loss Prevention Software

Vendor

• marcopiovanello

Name

• yt-dlp-web-ui

Version

• 4.0

Support

• end of life

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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