Improper input validation in Kaltura Html5 Video Player, Html5lib Library

CVE-2026-19913

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (43.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-19913: held from 0.004 to 0.005.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-19913?
CVE-2026-19913 is a high-severity vulnerability in Kaltura Html5 Video Player, Html5lib Library, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-08-25.
How severe is CVE-2026-19913?
High severity. CVSS v3 base score is 7.5 out of 10.