CVE-2026-100640 (GCVE-0-2026-100640)

Vulnerability from cvelistv5 – Published: 2026-09-26 13:23 – Updated: 2026-09-26 13:23
VLAI
Title
SiYuan before v3.8.4 Clipboard Data Disclosure via IPC
Summary
SiYuan before v3.8.4 contains an authorization omission in the siyuan-get IPC handler that allows remote-kernel renderers to access native clipboard formats by invoking clipboardReadMathML, clipboardReadOffice, and clipboardReadWPS commands with matching plaintext. Attackers controlling remote renderer content can obtain MathML formulas, Office bytes, and WPS bytes from local clipboard during user-mediated paste operations.
Severity
8.6 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
4.7 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
References
Impacted products
Vendor Product Version CPE status
siyuan-note siyuan Affected: 0 , < 3.8.4 (semver)
Unaffected: 3.8.4 (semver)
guessed Create a notification for this product.
Date Public
2026-09-10 00:00
Credits
rexpository
Show details on NVD website
To clipboard 

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        }
      ],
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            "Recovery": "NOT_DEFINED",
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            "baseScore": 8.6,
            "baseSeverity": "HIGH",
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            "providerUrgency": "NOT_DEFINED",
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              "description": "Exposure of Sensitive Information to an Unauthorized Actor",
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          "name": "GitHub Security Advisory (GHSA-mjmm-hgmc-m7qf)",
          "tags": [
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          "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-mjmm-hgmc-m7qf"
        },
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    "datePublished": "2026-09-26T13:23:13.287Z",
    "dateReserved": "2026-09-26T02:32:35.659Z",
    "dateUpdated": "2026-09-26T13:23:13.287Z",
    "state": "PUBLISHED"
  },
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          }
        ],
        "id": "CVE-2026-100640",
        "lastModified": "2026-09-26T14:16:46.020",
        "metrics": {
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                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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