CVE-2026-19913

Status: Awaiting AnalysisHigh (7.5)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Base score: 7.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.53%
Percentile among all scored CVEs: 43
Score date: 10/6/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1005 Data from Local Systemcollection90 %
Secondary impactT1552 Unsecured Credentialscredential access80 %

AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). El parámetro ServiceUrl no validado permite acceder a file:// y leer archivos arbitrarios del servidor reflejados en errores (T1005, T1552).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Limit Access to Resource Over Network Filter Network Traffic Update Software Active Directory Configuration Vulnerability Scanning

Affected technologies (2)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Kaltura — Html5lib^AI Kaltura — Mwembed^AI

CWEs

CWE-20, CWE-73

References

https://kb.cert.org/vuls/id/308749

Raw JSON (NVD)

Show

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        "ssvcData": {
          "id": "CVE-2026-19913",
          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
            },
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              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
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          "version": "2.0.3",
          "timestamp": "2026-08-26T12:51:07.833089Z"
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
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        "exploitabilityScore": 3.9
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  "affected": [
    {
      "source": "cret@cert.org",
      "affectedData": [
        {
          "vendor": "Kaltura",
          "product": "Kaltura HTML5 Video Player, html5lib library",
          "versions": [
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              "status": "affected",
              "version": "0",
              "versionType": "custom",
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            {
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  "published": "2026-08-25T17:17:09.163",
  "references": [
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    {
      "lang": "en",
      "value": "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."
    }
  ],
  "lastModified": "2026-09-03T17:38:29.613",
  "sourceIdentifier": "cret@cert.org"
}