CVE-2023-45818
mediumpriority · track · 24EPSS 0.008 · 55 %ileDEEUUSEPSS · scored 2026-10-27
TinyMCE is an open source rich text editor. A mutation cross-site scripting (mXSS) vulnerability was discovered in TinyMCE’s core undo and redo functionality. When a carefully-crafted HTML snippet passes the XSS sanitisation layer, it is manipulated as a string by internal trimming functions before being stored in the undo stack. If the HTML snippet is restored from the undo stack, the combination of the string manipulation and reparative parsing by either the browser's native [DOMParser API](https://developer.mozilla.org/en-US/docs/Web/API/DOMParser) (TinyMCE 6) or the SaxParser API (TinyMCE 5) mutates the HTML maliciously, allowing an XSS payload to be executed. This vulnerability has been patched in TinyMCE 5.10.8 and TinyMCE 6.7.1 by ensuring HTML is trimmed using node-level manipulation instead of string manipulation. Users are advised to upgrade. There are no known workarounds for this vulnerability.
cvss
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base score 0–10 · higher = more severe · hover a vector to decode
ssvc
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weaknesses
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affected products (10)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2024-0405IBM Maximo Asset Management: Mehrere Schwachstellen ermöglichen Cross-Site ScriptingDeutsch2024-02-15csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM Maximo Asset Management ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen.
- GHSA-v65r-p3vv-jjfvTinyMCE mXSS vulnerability in undo/redo, getContent API, resetContent API, and Autosave plugin2023-10-19ghsa · osvUS
### Impact A [mutation cross-site scripting](https://researchgate.net/publication/266654651_mXSS_attacks_Attacking_well-secured_web-applications_by_using_innerHTML_mutations) (mXSS) vulnerability was discovered in TinyMCE’s core undo and redo functionality. When a carefully-crafted HTML snippet passes the XSS sanitisation layer, it is manipulated as a string by internal trimming functions before being stored in the undo stack. If the HTML snippet is restored from the undo stack, the combination of the string manipulation and reparative parsing by either the browser's native [DOMParser API](https://developer.mozilla.org/en-US/docs/Web/API/DOMParser) (TinyMCE 6) or the [SaxParser API](https://www.tiny.cloud/docs/api/tinymce.html/tinymce.html.saxparser/) (TinyMCE 5) mutates the HTML maliciously, allowing an XSS payload to be executed. This vulnerability also impacts these related TinyMCE APIs and plugins: * [`tinymce.Editor.getContent({ format: 'raw' })`](https://tiny.cloud/docs/tinymce/6/apis/tinymce.editor/#getContent) * [`tinymce.Editor.resetContent()`](https://tiny.cloud/docs/tinymce/6/apis/tinymce.editor/#resetContent) * [Autosave Plugin](https://tiny.cloud/docs/tinymce/6/autosave/) ### Patches This vulnerability has been patched in TinyMCE 5.10.8 and TinyMCE 6.7.1 by ensuring HTML is trimmed using node-level manipulation instead of string manipulation. ### Fix To avoid this vulnerability: * Upgrade to TinyMCE 5.10.8 or higher for TinyMCE 5.x. * Upgrade to TinyMCE 6.7.1 or higher for TinyMCE 6.x. ### Acknowledgements Tiny Technologies would like to thank Masato Kinugawa of [Cure53](https://cure53.de/) for discovering this vulnerability. ### References * [TinyMCE 5.10.8 Release Notes](https://tiny.cloud/docs/release-notes/release-notes5108/) * [TinyMCE 6.7.1 Release Notes](https://tiny.cloud/docs/tinymce/6/6.7.1-release-notes/) ### For more information If you have any questions or comments about this advisory: * Email us at <infosec@tiny.cloud> * Open an issue in the [TinyMCE repo](https://github.com/tinymce/tinymce/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc)
also known as (3)
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sources
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references (16)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2023-45818/cnnvd
- https://github.com/tinymce/tinymce/security/advisories/GHSA-v65r-p3vv-jjfvcnnvd
- https://researchgate.net/publication/266654651_mXSS_attacks_Attacking_well-secured_web-applications_by_using_innerHTML_mutationscnnvd
- https://tiny.cloud/docs/release-notes/release-notes5108/#securityfixescnnvd
- https://tiny.cloud/docs/tinymce/6/6.7.1-release-notes/#security-fixescnnvd
- https://www.tiny.cloud/docs/api/tinymce.html/tinymce.html.saxparser/cnnvd
- https://github.com/tinymce/tinymce/security/advisories/GHSA-v65r-p3vv-jjfvenisa_euvd
- https://researchgate.net/publication/266654651_mXSS_attacks_Attacking_well-secured_web-applications_by_using_innerHTML_mutationsenisa_euvd
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