Vulnerability-Lookup

GHSA-RHVG-PC25-4R8P

Vulnerability from github – Published: 2026-09-08 15:31 – Updated: 2026-09-08 15:31

Details

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."

Severity

3.5 (Low)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

2.0 (Low)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

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{
  "affected": [],
  "aliases": [
    "CVE-2026-86644"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-08T14:17:35Z",
    "severity": "LOW"
  },
  "details": "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.\"",
  "id": "GHSA-rhvg-pc25-4r8p",
  "modified": "2026-09-08T15:31:56Z",
  "published": "2026-09-08T15:31:56Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86644"
    },
    {
      "type": "WEB",
      "url": "https://github.com/star7th/showdoc/commit/a8ea1520850b4242f395247f72e87e597506cef0"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/saDL0w/36a72a076e9ab24408a3d27582e778b2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/star7th/showdoc"
    },
    {
      "type": "WEB",
      "url": "https://github.com/star7th/showdoc/releases/tag/v3.9.2"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/cve/CVE-2026-86644"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/submit/906282"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/399755"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/399755/cti"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-86644 (GCVE-0-2026-86644)

Vulnerability from cvelistv5 – Published: 2026-09-08 13:30 – Updated: 2026-09-08 15:42 X_Open Source

Title

star7th showdoc API Page Save Endpoint editormd.js cross site scripting

Summary

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."

Severity

5.1 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

3.5 (Low)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

3.5 (Low)


                        
                          CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 15:42 UTC

CWE

CWE-79 - Cross Site Scripting
CWE-94 - Code Injection

Assigner

VulDB mitre root

References

8 references

URL	Tags
https://vuldb.com/vuln/399755	vdb-entry
https://vuldb.com/vuln/399755/cti	signaturepermissions-required
https://vuldb.com/cve/CVE-2026-86644	third-party-advisory
https://vuldb.com/submit/906282	third-party-advisory
https://gist.github.com/saDL0w/36a72a076e9ab24408…	exploit
https://github.com/star7th/showdoc/commit/a8ea152…	patch
https://github.com/star7th/showdoc/releases/tag/v3.9.2	patch
https://github.com/star7th/showdoc/	product

Impacted products

1 product

Vendor	Product	Version
star7th	showdoc	Affected: 3.9.0 Affected: 3.9.1 Unaffected: 3.9.2 cpe:2.3:a:showdoc:showdoc::::::::

Credits

LIU Tingwei (VulDB User) VulDB CNA Team

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JSON

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                  },
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      "credits": [
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          "value": "VulDB entry created"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-RHVG-PC25-4R8P

CVE-2026-86644 (GCVE-0-2026-86644)

Tags

Sightings

Nomenclature