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."

CVSS v3 3.5 LOW
CVSS v2.0 4.0 MEDIUM

3.5^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.1 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

4.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:S/C:N/I:P/A:N

Exploitability : 8.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-08 14:17

Updated : 2026-09-08 18:33

NVD link : CVE-2026-86644

Mitre link : CVE-2026-86644

CVE.ORG link : CVE-2026-86644

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-94

Improper Control of Generation of Code ('Code Injection')

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