Vulnerability-Lookup

GHSA-962C-HGX6-FFMX

Vulnerability from github – Published: 2026-08-19 15:32 – Updated: 2026-08-19 15:32

Details

SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '((' block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block's name, alias, and memo fields are concatenated into the popup's HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. ) that executes automatically when a victim types '((' followed by a search term that surfaces the crafted block. Because SiYuan's Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require('child_process') access, allowing the XSS to escalate to arbitrary OS command execution.

Severity

8.6 (High)


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

9.3 (Critical)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-75916"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-19T14:17:41Z",
    "severity": "CRITICAL"
  },
  "details": "SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the \u0027((\u0027 block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block\u0027s name, alias, and memo fields are concatenated into the popup\u0027s HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. \u003cimg src=x onerror=...\u003e) that executes automatically when a victim types \u0027((\u0027 followed by a search term that surfaces the crafted block. Because SiYuan\u0027s Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require(\u0027child_process\u0027) access, allowing the XSS to escalate to arbitrary OS command execution.",
  "id": "GHSA-962c-hgx6-ffmx",
  "modified": "2026-08-19T15:32:28Z",
  "published": "2026-08-19T15:32:28Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75916"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/siyuan-xss-to-rce-via-unescaped-block-metadata-in-hint-popup"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/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-2026-75916 (GCVE-0-2026-75916)

Vulnerability from cvelistv5 – Published: 2026-08-19 14:01 – Updated: 2026-08-19 14:01

Title

SiYuan XSS-to-RCE via unescaped block metadata in hint popup

Summary

SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '((' block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block's name, alias, and memo fields are concatenated into the popup's HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. <img src=x onerror=...>) that executes automatically when a victim types '((' followed by a search term that surfaces the crafted block. Because SiYuan's Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require('child_process') access, allowing the XSS to escalate to arbitrary OS command execution.

Severity

9.3 (Critical)


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

8.6 (High)


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

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/siyuan-note/siyuan/security/ad…	vendor-advisory
https://www.vulncheck.com/advisories/siyuan-xss-t…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
siyuan-note	siyuan	cpe:2.3:a:b3log:siyuan:-:::::::*

Date Public

2026-08-05 00:00

Credits

alham-rizvi hey-raghav

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "packageURL": "pkg:npm/siyuan",
          "product": "siyuan",
          "vendor": "siyuan-note"
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:b3log:siyuan:-:*:*:*:*:*:*:*",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "alham-rizvi"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "hey-raghav"
        }
      ],
      "datePublic": "2026-08-05T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the \u0027((\u0027 block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block\u0027s name, alias, and memo fields are concatenated into the popup\u0027s HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. \u003cimg src=x onerror=...\u003e) that executes automatically when a victim types \u0027((\u0027 followed by a search term that surfaces the crafted block. Because SiYuan\u0027s Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require(\u0027child_process\u0027) access, allowing the XSS to escalate to arbitrary OS command execution."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 8.6,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-19T14:01:50.370Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-5prr-vgxq-69g9)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9"
        },
        {
          "name": "VulnCheck Advisory: SiYuan XSS-to-RCE via unescaped block metadata in hint popup",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/siyuan-xss-to-rce-via-unescaped-block-metadata-in-hint-popup"
        }
      ],
      "title": "SiYuan XSS-to-RCE via unescaped block metadata in hint popup",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-75916",
    "datePublished": "2026-08-19T14:01:50.370Z",
    "dateReserved": "2026-08-18T15:05:54.226Z",
    "dateUpdated": "2026-08-19T14:01:50.370Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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-962C-HGX6-FFMX

CVE-2026-75916 (GCVE-0-2026-75916)

Tags

Sightings

Nomenclature