CVE-2026-109966
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.
Does this matter?
Lower severity and a low EPSS score (0.41%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 4.0
- 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.41% probability · 35th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-88
- Source
- disclosure@vulncheck.com
EPSS moved from 0.4% on 14 October 2026 to 0.4% on 26 October 2026.
References
- https://github.com/marcopiovanello/yt-dlp-web-ui
- https://github.com/marcopiovanello/yt-dlp-web-ui/blob/v4.0.0/server/formats/parser.go
- https://github.com/vazzzy071-crypto/security-advisories/blob/main/advisories/2026-10-marcopiovanello-yt-dlp-web-ui-rpc-arg-injection.md
- https://www.vulncheck.com/advisories/yt-dlp-web-ui-through-4.0.0-argument-injection-via-service-formats-json-rpc-method
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.