CVE-2026-108839 (GCVE-0-2026-108839)

Vulnerability from cvelistv5 – Published: 2026-10-11 13:26 – Updated: 2026-10-11 13:26
VLAI
Title
thClaws through 0.141.0 Symlink Following File Write via POST /v1/inputs
Summary
thClaws through 0.141.0 contains a link-following vulnerability in the post_inputs handler of the v1 API POST /v1/inputs endpoint that allows writes outside the workspace by following symlinks. Attackers who plant a symlink under the allowed inputs/ prefix can cause later authenticated uploads to write or truncate files outside the workspace with daemon privileges.
Severity
2.3 (Low)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
4.2 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 5955 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
thClaws thClaws Affected: 0 , ≤ 0.141.0 (semver)
guessed Create a notification for this product.
Date Public
2026-10-11 00:00
Credits
hieuPenguinnn
Show details on NVD website
To clipboard 

{
  "containers": {
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        {
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          "packageURL": "pkg:github/thClaws/thClaws",
          "product": "thClaws",
          "repo": "https://github.com/thClaws/thClaws",
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          "versions": [
            {
              "lessThanOrEqual": "0.141.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
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          "type": "finder",
          "value": "hieuPenguinnn"
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      ],
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        }
      ],
      "metrics": [
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            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
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            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
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            "vulnIntegrityImpact": "LOW"
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            "userInteraction": "REQUIRED",
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            "version": "3.1"
          },
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        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-59",
              "description": "Improper Link Resolution Before File Access (\u0027Link Following\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-11T13:26:00.141Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "tags": [
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          ],
          "url": "https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/thclaws-api-inputs-symlink-escape"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/thClaws/thClaws/blob/v0.141.0/crates/core/src/api_v1/artifacts.rs#L335-L420"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/thClaws/thClaws"
        },
        {
          "name": "VulnCheck Advisory: thClaws through 0.141.0 Symlink Following File Write via POST /v1/inputs",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/thclaws-through-0.141.0-symlink-following-file-write-via-post-v1-inputs"
        }
      ],
      "title": "thClaws through 0.141.0 Symlink Following File Write via POST /v1/inputs",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-108839",
    "datePublished": "2026-10-11T13:26:00.141Z",
    "dateReserved": "2026-10-11T12:50:50.838Z",
    "dateUpdated": "2026-10-11T13:26:00.141Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
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      "date": "2026-10-14",
      "epss": "0.00251",
      "percentile": "0.15311"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "packageURL": "pkg:github/thClaws/thClaws",
                "product": "thClaws",
                "repo": "https://github.com/thClaws/thClaws",
                "vendor": "thClaws",
                "versions": [
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                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  }
                ]
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            ],
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        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "thClaws through 0.141.0 contains a link-following vulnerability in the post_inputs handler of the v1 API POST /v1/inputs endpoint that allows writes outside the workspace by following symlinks. Attackers who plant a symlink under the allowed inputs/ prefix can cause later authenticated uploads to write or truncate files outside the workspace with daemon privileges."
          }
        ],
        "id": "CVE-2026-108839",
        "lastModified": "2026-10-11T14:17:04.390",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "HIGH",
                "attackVector": "NETWORK",
                "availabilityImpact": "LOW",
                "baseScore": 4.2,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "REQUIRED",
                "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L",
                "version": "3.1"
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            }
          ],
          "cvssMetricV40": [
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              "cvssData": {
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                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
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                "attackRequirements": "PRESENT",
                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
                "baseScore": 2.3,
                "baseSeverity": "LOW",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "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",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "PASSIVE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:L/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",
                "version": "4.0",
                "vulnAvailabilityImpact": "LOW",
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                "vulnIntegrityImpact": "LOW",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
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              "source": "disclosure@vulncheck.com",
              "type": "Secondary"
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        "references": [
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://github.com/thClaws/thClaws"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://github.com/thClaws/thClaws/blob/v0.141.0/crates/core/src/api_v1/artifacts.rs#L335-L420"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/thclaws-api-inputs-symlink-escape"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://www.vulncheck.com/advisories/thclaws-through-0.141.0-symlink-following-file-write-via-post-v1-inputs"
          }
        ],
        "sourceIdentifier": "disclosure@vulncheck.com",
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            "type": "Primary"
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    }
  }
}



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