Vulnerability-Lookup

GHSA-8R4C-C246-MWJC

Vulnerability from github – Published: 2026-09-26 15:31 – Updated: 2026-09-26 15:31

Details

SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim's browser.

Severity

7.6 (High)


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

7.2 (High)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-100642"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-346"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-26T14:16:46Z",
    "severity": "HIGH"
  },
  "details": "SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim\u0027s browser.",
  "id": "GHSA-8r4c-c246-mwjc",
  "modified": "2026-09-26T15:31:17Z",
  "published": "2026-09-26T15:31:17Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-100642"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/siyuan-2.1.0-before-3.8.4-cross-site-request-forgery-via-checkauth"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/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-2026-100642 (GCVE-0-2026-100642)

Vulnerability from cvelistv5 – Published: 2026-09-26 13:23 – Updated: 2026-09-26 13:23

Title

SiYuan v2.1.0 before v3.8.4 Cross-Site Request Forgery via CheckAuth

Summary

Severity

7.2 (High)


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

7.6 (High)


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

CWE

CWE-346 - Origin Validation Error

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-2.1.0…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
siyuan-note	siyuan	Affected: 2.1.0 , < 3.8.4 (semver) Unaffected: 3.8.4 (semver) cpe:2.3:a:b3log:siyuan::::::::

Date Public

2026-09-10 00:00

Credits

Yanhaoxi

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "siyuan",
          "vendor": "siyuan-note",
          "versions": [
            {
              "lessThan": "3.8.4",
              "status": "affected",
              "version": "2.1.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "3.8.4",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "3.8.4",
                  "versionStartIncluding": "2.1.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Yanhaoxi"
        }
      ],
      "datePublic": "2026-09-10T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "SiYuan versions from v2.1.0 before v3.8.4 contain a cross-site request forgery vulnerability in the CheckAuth lock-screen pass-through branch that grants administrator access to loopback requests without validating Origin headers. Attackers can craft malicious web pages that force victims to terminate the kernel process, read workspace configuration and proxy settings, and trigger administrative actions via zero-credential cross-origin requests from the victim\u0027s browser."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 7.2,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.6,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-346",
              "description": "Origin Validation Error",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-26T13:23:14.649Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-9gpj-3rm3-x42m)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9gpj-3rm3-x42m"
        },
        {
          "name": "VulnCheck Advisory: SiYuan v2.1.0 before v3.8.4 Cross-Site Request Forgery via CheckAuth",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/siyuan-2.1.0-before-3.8.4-cross-site-request-forgery-via-checkauth"
        }
      ],
      "title": "SiYuan v2.1.0 before v3.8.4 Cross-Site Request Forgery via CheckAuth",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-100642",
    "datePublished": "2026-09-26T13:23:14.649Z",
    "dateReserved": "2026-09-26T02:32:35.659Z",
    "dateUpdated": "2026-09-26T13:23:14.649Z",
    "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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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GHSA-8R4C-C246-MWJC

CVE-2026-100642 (GCVE-0-2026-100642)

Tags

Sightings

Nomenclature

Related by attack behaviour