CVE-2026-86644
A vulnerability was determined in star7th showdoc up to 3.9.1. This vulnerability affects unknown code of the file web_src/public/editor.md/editormd.js of the component API Page Save Endpoint. Executing a manipulation can lead to cross site scripting. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 3.9.2 is able to resolve this issue. This patch is called a8ea1520850b4242f395247f72e87e597506cef0. Upgrading the affected component is recommended. The vendor confirms: "The fix [...] sets Mermaid `securityLevel` to `strict`, disables `htmlLabels`, and sanitizes rendered SVG with DOMPurify."
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 3.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N- CVSS v4
- 2.0
- Weakness
- CWE-79
- Assigned by
- cna@vuldb.com
Dates
- Published
- 2026-09-08
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://gist.github.com/saDL0w/36a72a076e9ab24408a3d27582e778b2
- https://github.com/star7th/showdoc/
- https://github.com/star7th/showdoc/commit/a8ea1520850b4242f395247f72e87e597506cef0
- https://github.com/star7th/showdoc/releases/tag/v3.9.2
- https://vuldb.com/cve/CVE-2026-86644
- https://vuldb.com/submit/906282
- https://vuldb.com/vuln/399755
- https://vuldb.com/vuln/399755/cti