Vulnerability · Published Aug 25, 2026 · Assigned by certcc
CVE-2026-19913CVE-2026-19913
High 7.5
In plain English
A high-severity improper input validation in Kaltura HTML5 Video Player, html5lib library from Kaltura. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official description
The Kaltura HTML5 player (mwEmbed / html5lib) contains a local file disclosure vulnerability due to improper validation of the ServiceUrl parameter in mwEmbedLoader.php. This parameter is used as the base URL for a backend request and accepts non‑HTTP schemes such as file://. When an exception or error occurs, the response is subsequently deserialized and its raw contents are reflected to the client in an error message; this enables an unauthenticated, remote attacker to read any arbitrary internal file reachable by the server. Affected versions include html5lib v2.45, v2.103 and earlier, and other v2.x releases exposing the vulnerable endpoint.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Kaltura | Kaltura HTML5 Video Player, html5lib library | 0 – through v2.1032.45 |
Weakness: CWE-20, CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N