CVE-2026-19912 | defend.network

What is CVE-2026-19912?

The Kaltura HTML5 player (mwEmbed / html5lib) contains an unauthenticated remote code execution vulnerability caused by unsafe data deserialization and unsanitized filesystem path construction. mwEmbedLoader.php accepts a user‑controlled ServiceUrl, whose response is passed to unserialize(), and the resulting object’s fields are written to a cache path derived from attacker‑supplied uiconf_id without proper path validation. An attacker can write arbitrary files into web‑accessible locations and achieve code execution as the webserver user. Affected versions include html5lib v2.45, v2.103 and earlier, and other v2.x releases exposing the vulnerable endpoint.

CVSSawaiting NVD

ExploitationNo exploitation reported

EPSS<1% · P13

Triage statusUnder Review

ActionSchedule for next cycle

NVD published2026-08-25

NVD last modified2026-08-25

Timeline

2026-08-25Published to the U.S. National Vulnerability Database (NVD)
2026-08-27First covered in a defend.network daily briefing

Affected product

See advisory

Remediation Steps

Identify all instances of Kaltura mwEmbed deployed in your environment
Contact Kaltura or monitor their security advisories for available patches
Apply vendor patches as soon as released
Restrict unauthenticated access to the mwEmbedLoader.php endpoint where feasible

References

Referenced in our briefings & reports

Vulnerability Priority Report – Week 4 of August 2026 (August 24 – 30)
Chinese infrastructure disrupted; Kaltura RCE unpatched; NovaCookies targets Microsoft 365 (2026-08-27)

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🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.