Vulnerability-Lookup

GHSA-6W77-CP2C-MFXQ

Vulnerability from github – Published: 2026-05-10 15:31 – Updated: 2026-05-10 15:31

Details

OpenCATS 0.9.4 contains a remote code execution vulnerability that allows unauthenticated attackers to execute arbitrary commands by uploading malicious PHP files disguised as resume attachments. Attackers can upload PHP payloads through the careers job application endpoint and execute system commands via POST requests to the uploaded file in the upload directory.

Severity

9.8 (Critical)


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

9.3 (Critical)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47936"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-306"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-10T13:16:29Z",
    "severity": "CRITICAL"
  },
  "details": "OpenCATS 0.9.4 contains a remote code execution vulnerability that allows unauthenticated attackers to execute arbitrary commands by uploading malicious PHP files disguised as resume attachments. Attackers can upload PHP payloads through the careers job application endpoint and execute system commands via POST requests to the uploaded file in the upload directory.",
  "id": "GHSA-6w77-cp2c-mfxq",
  "modified": "2026-05-10T15:31:19Z",
  "published": "2026-05-10T15:31:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47936"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencats/OpenCATS"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/50585"
    },
    {
      "type": "WEB",
      "url": "https://www.opencats.org"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/opencats-remote-code-execution-via-resume-upload"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/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-2021-47936 (GCVE-0-2021-47936)

Vulnerability from cvelistv5 – Published: 2026-05-10 12:43 – Updated: 2026-05-11 15:17

Title

OpenCATS 0.9.4 Remote Code Execution via Resume Upload

Summary

Severity

9.3 (Critical)


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

9.8 (Critical)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-11 15:16 UTC

CWE

CWE-306 - Missing Authentication for Critical Function

Assigner

VulnCheck CNA under the mitre root

CNA scorecard B 84/100 over 6614 records in the last 180 days details

References

4 references

URL	Tags
https://www.exploit-db.com/exploits/50585	exploit
https://www.opencats.org/	product
https://github.com/opencats/OpenCATS	product
https://www.vulncheck.com/advisories/opencats-rem…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Opencats	OpenCATS	Affected: 0 , ≤ 0.9.4 (custom) cpe:2.3:a:opencats:opencats::::::::

Credits

Nicholas Ferreira - https://github.com/Nickguitar

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47936",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-11T15:16:56.979826Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-11T15:17:07.720Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "OpenCATS",
          "vendor": "Opencats",
          "versions": [
            {
              "lessThanOrEqual": "0.9.4",
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          ]
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      ],
      "cpeApplicability": [
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                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
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          "lang": "en",
          "type": "finder",
          "value": "Nicholas Ferreira - https://github.com/Nickguitar"
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          "lang": "en",
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        }
      ],
      "metrics": [
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            "Recovery": "NOT_DEFINED",
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            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
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          "tags": [
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        },
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    "datePublished": "2026-05-10T12:43:54.993Z",
    "dateReserved": "2026-02-01T11:24:18.717Z",
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}

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.

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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.
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