Vulnerability-Lookup

GHSA-6PH4-R249-58P2

Vulnerability from github – Published: 2026-09-08 00:30 – Updated: 2026-09-08 00:30

Details

knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary path is executed twice under the user's account without any verification.

Severity

7.8 (High)


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

8.5 (High)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-86540"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-78"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-07T23:16:53Z",
    "severity": "HIGH"
  },
  "details": "knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary path is executed twice under the user\u0027s account without any verification.",
  "id": "GHSA-6ph4-r249-58p2",
  "modified": "2026-09-08T00:30:22Z",
  "published": "2026-09-08T00:30:22Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/knowns-dev/knowns/security/advisories/GHSA-mc52-mwq4-vfx3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86540"
    },
    {
      "type": "WEB",
      "url": "https://github.com/knowns-dev/knowns/commit/d3989829fb5095666d23d005b2f78a082832a396"
    },
    {
      "type": "WEB",
      "url": "https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/lsp/detect.go#L128-L157"
    },
    {
      "type": "WEB",
      "url": "https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/models/config.go#L205-L216"
    },
    {
      "type": "WEB",
      "url": "https://github.com/knowns-dev/knowns/releases/tag/v0.30.0"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/knowns-before-0.30.0-arbitrary-code-execution-via-lsp-binary"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/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: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-2026-86540 (GCVE-0-2026-86540)

Vulnerability from cvelistv5 – Published: 2026-09-07 23:03 – Updated: 2026-09-24 14:21

Title

knowns before 0.30.0 Arbitrary Code Execution via LSP Binary

Summary

Severity

8.5 (High)


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

7.8 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 13:48 UTC

CWE

CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Assigner

VulnCheck mitre root Scorecard

References

6 references

URL	Tags
https://github.com/knowns-dev/knowns/security/adv…	vendor-advisory
https://github.com/knowns-dev/knowns/blob/v0.29.1…	technical-description
https://github.com/knowns-dev/knowns/blob/v0.29.1…	technical-description
https://github.com/knowns-dev/knowns/commit/d3989…	patch
https://github.com/knowns-dev/knowns/releases/tag…	release-notes
https://www.vulncheck.com/advisories/knowns-befor…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
knowns-dev	knowns	Affected: 0 , < 0.30.0 (semver) Unaffected: 0.30.0 (semver)

Date Public

2026-08-16 00:00

Credits

Tong Hoang Gia (uziii2208) Nguyen Huy Hoang (hoanggxyuuki)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-86540",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-08T13:48:43.528505Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
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        "providerMetadata": {
          "dateUpdated": "2026-09-08T13:48:56.891Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "defaultStatus": "unaffected",
          "packageURL": "pkg:npm/knowns",
          "product": "knowns",
          "vendor": "knowns-dev",
          "versions": [
            {
              "lessThan": "0.30.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "0.30.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Tong Hoang Gia (uziii2208)"
        },
        {
          "lang": "en",
          "type": "finder",
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        }
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      "datePublic": "2026-08-16T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "knowns versions before 0.30.0 fail to validate the settings.lsp.languages binary field in project configuration files, allowing attackers to execute arbitrary binaries by crafting a malicious .knowns/config.json file. When a repository with a crafted configuration is opened, the unvalidated binary path is executed twice under the user\u0027s account without any verification."
        }
      ],
      "metrics": [
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          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 8.5,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
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            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
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            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
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        },
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          "name": "Detector.resolve executes the unvalidated binary override (v0.29.1)",
          "tags": [
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          "url": "https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/lsp/detect.go#L128-L157"
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          "name": "ProjectSettings.Validate does not inspect the LSP binary field (v0.29.1)",
          "tags": [
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          "url": "https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/models/config.go#L205-L216"
        },
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          "name": "knowns fix commit d3989829fb50",
          "tags": [
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        },
        {
          "name": "knowns v0.30.0 Release Notes",
          "tags": [
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          ],
          "url": "https://github.com/knowns-dev/knowns/releases/tag/v0.30.0"
        },
        {
          "name": "VulnCheck Advisory: knowns before 0.30.0 Arbitrary Code Execution via LSP Binary",
          "tags": [
            "third-party-advisory"
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          "url": "https://www.vulncheck.com/advisories/knowns-before-0.30.0-arbitrary-code-execution-via-lsp-binary"
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    "datePublished": "2026-09-07T23:03:18.654Z",
    "dateReserved": "2026-09-07T22:18:47.705Z",
    "dateUpdated": "2026-09-24T14:21:24.010Z",
    "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.

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GHSA-6PH4-R249-58P2

CVE-2026-86540 (GCVE-0-2026-86540)

Tags

Sightings

Nomenclature

Related by attack behaviour