CVE-2026-57440
Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled
The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
7.5
Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled
The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.
- Record
CVE-2026-57440- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
EUVDEUVD-2026-86396
7.5
The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.
- Record
EUVD-2026-86396- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-v65j-hff3-753c
7.5
Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled
Summary
With $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection.
Details
The iframe assembled here adds the url from getUrl() as the src without sanitization.
The id regex for the archiveorg service and the url regexes for the wistia and sharepoint services allow for double quotes to be introduced.
PoC
Using double quotes, the src attribute can be escaped.
<embedvideo service="archiveorg" id='a" onmouseover="alert(document.domain)" data-x="'></embedvideo>
Impact
When $wgEmbedVideoRequireConsent = false, any user able to edit a page can inject arbitrary JavaScript into an HTML event handler attribute (e.g. onfocus) via parameter. It requires no interaction (autofires via autofocus) and executes in the wiki origin for every visitor to the page.
- Record
GHSA-v65j-hff3-753c- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
NVD
7.5
The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.
- Record
CVE-2026-57440- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
OSV
7.5
Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled
The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. Prior to 4.1.0, with $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection. Version 4.1.0 contains a patch.
- Record
CVE-2026-57440- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
OSVGHSA-v65j-hff3-753c
7.5
Mediawiki EmbedVideo Extension has stored XSS via malformed src url with $wgEmbedVideoRequireConsent disabled
Summary
With $wgEmbedVideoRequireConsent disabled (not the default), the urls for videos are passed into an iframe src attribute without sanitization. When given a malformed url or id, the src attribute can be escaped via double quotes, allowing for html/javascript injection.
Details
The iframe assembled here adds the url from getUrl() as the src without sanitization.
The id regex for the archiveorg service and the url regexes for the wistia and sharepoint services allow for double quotes to be introduced.
PoC
Using double quotes, the src attribute can be escaped.
<embedvideo service="archiveorg" id='a" onmouseover="alert(document.domain)" data-x="'></embedvideo>
Impact
When $wgEmbedVideoRequireConsent = false, any user able to edit a page can inject arbitrary JavaScript into an HTML event handler attribute (e.g. onfocus) via parameter. It requires no interaction (autofires via autofocus) and executes in the wiki origin for every visitor to the page.
- Record
GHSA-v65j-hff3-753c- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
starcitizenwiki/embedvideoPackagist |
through 4.0.0 | 4.1.0 |
starcitizenwiki/embedvideoPackagist |
before 4.1.0, plus listed versions 3.0.03.0.13.0.23.0.33.0.4 Show 21 moreShow less3.0.53.0.63.0.73.0.83.0.93.1.03.2.03.2.13.2.23.2.33.2.43.2.53.2.63.2.73.2.83.3.03.4.03.4.13.4.23.4.34.0.0 |
4.1.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-57440 is a high vulnerability (CVSS 7.5) in Starcitizenwiki Mediawiki-extensions-embedvideo, published September 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 26th percentile. Fixed in starcitizenwiki/embedvideo 4.1.0.
References
github.com/StarCitizenWiki/mediawiki-extensions-EmbedVideo/security/advisories/GHSA-v65j-hff3-753c
github.com/StarCitizenWiki/mediawiki-extensions-EmbedVideo/commit/370156335b325bb81d14d89edf0a1f2643d50a84
nvd.nist.gov/vuln/detail/CVE-2026-57440
github.com/advisories/GHSA-v65j-hff3-753c
github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57440.json
github.com/StarCitizenWiki/mediawiki-extensions-EmbedVideo