Vulnerability-Lookup

CVE-2026-27891 (GCVE-0-2026-27891)

Vulnerability from cvelistv5 – Published: 2026-05-18 21:16 – Updated: 2026-05-19 13:41

Title

Remote Code Execution (RCE) via Zip Slip in Plugin Upload Mechanism

Summary

FacturaScripts is an open source accounting and invoicing software. Versions 2026 and below contain a critical vulnerability in the Plugins::add() function. The system fails to properly validate the file paths within uploaded ZIP archives. This allows an attacker to perform a Zip Slip attack, leading to Arbitrary File Write and Remote Code Execution (RCE) by overwriting sensitive .php files outside the designated plugins directory. The vulnerability is located in Plugins.php. While the testZipFile function attempts to validate that the ZIP contains only one root folder, it does not sanitize or validate the individual file paths within that folder. An attacker can bypass this check by naming a file ValidPluginName/../../shell.php. The explode function will see ValidPluginName as the root folder, satisfying the count($folders) != 1 check. However, during extraction, the ../../ sequence triggers a path traversal, allowing the file to be written anywhere the web server has permissions the root directory. This issue is fixed in version 2026.1.

Severity

7.2 (High)


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

CWE

CWE-20 - Improper Input Validation
CWE-434 - Unrestricted Upload of File with Dangerous Type

Assigner

GitHub_M

References

2 references

URL	Tags
https://github.com/NeoRazorX/facturascripts/secur…	x_refsource_CONFIRM
https://github.com/NeoRazorX/facturascripts/commi…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
NeoRazorX	facturascripts	Affected: < 2026.1

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-27891

Vulnerability from fkie_nvd - Published: 2026-05-18 22:16 - Updated: 2026-05-19 15:16

Severity

7.2 (High) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/NeoRazorX/facturascripts/commit/2dda7c6f3b241fa84a0629166783720b882725fd
	security-advisories@github.com	https://github.com/NeoRazorX/facturascripts/security/advisories/GHSA-3pgc-xqg9-cfr6
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/NeoRazorX/facturascripts/security/advisories/GHSA-3pgc-xqg9-cfr6

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "FacturaScripts is an open source accounting and invoicing software. Versions 2026 and below contain a critical vulnerability in the Plugins::add() function. The system fails to properly validate the file paths within uploaded ZIP archives. This allows an attacker to perform a Zip Slip attack, leading to Arbitrary File Write and Remote Code Execution (RCE) by overwriting sensitive .php files outside the designated plugins directory. The vulnerability is located in Plugins.php. While the testZipFile function attempts to validate that the ZIP contains only one root folder, it does not sanitize or validate the individual file paths within that folder. An attacker can bypass this check by naming a file ValidPluginName/../../shell.php. The explode function will see ValidPluginName as the root folder, satisfying the count($folders) != 1 check. However, during extraction, the ../../ sequence triggers a path traversal, allowing the file to be written anywhere the web server has permissions the root directory. This issue is fixed in version 2026.1."
    }
  ],
  "id": "CVE-2026-27891",
  "lastModified": "2026-05-19T15:16:27.463",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.2,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-05-18T22:16:38.370",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/NeoRazorX/facturascripts/commit/2dda7c6f3b241fa84a0629166783720b882725fd"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/NeoRazorX/facturascripts/security/advisories/GHSA-3pgc-xqg9-cfr6"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/NeoRazorX/facturascripts/security/advisories/GHSA-3pgc-xqg9-cfr6"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        },
        {
          "lang": "en",
          "value": "CWE-434"
        }
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      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-3PGC-XQG9-CFR6

Vulnerability from github – Published: 2026-05-07 19:32 – Updated: 2026-05-07 19:32

Summary

FacturaScripts Vulnerable to Remote Code Execution (RCE) via Zip Slip in Plugin Upload Mechanism

Details

Summary

A Critical vulnerability exists in the Plugins::add() function. The system fails to properly validate the file paths within uploaded ZIP archives. This allows an attacker to perform a Zip Slip attack, leading to Arbitrary File Write and Remote Code Execution (RCE) by overwriting sensitive .php files outside the designated plugins directory.

Details

The vulnerability is located in Plugins.php. While the testZipFile function attempts to validate that the ZIP contains only one root folder, it does not sanitize or validate the individual file paths within that folder.

// Vulnerable logic in Plugins.php
for ($index = 0; $index < $zipFile->numFiles; $index++) {
    $data = $zipFile->statIndex($index);
    $path = explode('/', $data['name']);
    if (count($path) > 1) {
        $folders[$path[0]] = $path[0];
    }
}

An attacker can bypass this check by naming a file ValidPluginName/../../shell.php. The explode function will see ValidPluginName as the root folder, satisfying the count($folders) != 1 check. However, during extraction, the ../../ sequence triggers a path traversal, allowing the file to be written anywhere the web server has permissions the root directory.

PoC

Prepare Malicious ZIP: Use a tool (like evilarc) or a script to create a ZIP file where one of the entries is named: MyPlugin/../../rce.php Inject Payload: Inside rce.php, put a simple shell: <?php system($_GET['cmd']); ?> Upload: Navigate to the "Add Plugin" section in FacturaScripts and upload the malicious ZIP. Execution: Access the shell via https://target.com/rce.php?cmd=whoami.

Impact

Confidentiality: High (Attacker can read all database configs and files). Integrity: High (Attacker can modify any file on the server). Availability: High (Attacker can delete the entire installation).

https://github.com/ZeroXJacks/CVEs/blob/main/2026/CVE-2026-27891.md

Severity

7.2 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "facturascripts/facturascripts"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "2025.71"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-27891"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-434"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-07T19:32:14Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nA Critical vulnerability exists in the `Plugins::add()` function. The system fails to properly validate the file paths within uploaded ZIP archives. This allows an attacker to perform a Zip Slip attack, leading to Arbitrary File Write and Remote Code Execution (RCE) by overwriting sensitive .php files outside the designated plugins directory.\n\n### Details\nThe vulnerability is located in Plugins.php. While the `testZipFile` function attempts to validate that the ZIP contains only one root folder, it does not sanitize or validate the individual file paths within that folder.\n```js\n// Vulnerable logic in Plugins.php\nfor ($index = 0; $index \u003c $zipFile-\u003enumFiles; $index++) {\n    $data = $zipFile-\u003estatIndex($index);\n    $path = explode(\u0027/\u0027, $data[\u0027name\u0027]);\n    if (count($path) \u003e 1) {\n        $folders[$path[0]] = $path[0];\n    }\n} \n```\nAn attacker can bypass this check by naming a file `ValidPluginName/../../shell.php`. The explode function will see ValidPluginName as the root folder, satisfying the `count($folders) != 1` check. However, during extraction, the `../../` sequence triggers a path traversal, allowing the file to be written anywhere the web server has permissions the root directory.\n### PoC\nPrepare Malicious ZIP: Use a tool (like evilarc) or a script to create a ZIP file where one of the entries is named: `MyPlugin/../../rce.php`\nInject Payload: Inside rce.php, put a simple shell: \n`\u003c?php system($_GET[\u0027cmd\u0027]); ?\u003e`\nUpload: Navigate to the \"Add Plugin\" section in FacturaScripts and upload the malicious ZIP.\nExecution: Access the shell via https://target.com/rce.php?cmd=whoami.\n\n### Impact\nConfidentiality: High (Attacker can read all database configs and files).\nIntegrity: High (Attacker can modify any file on the server).\nAvailability: High (Attacker can delete the entire installation).\n\u003e https://github.com/ZeroXJacks/CVEs/blob/main/2026/CVE-2026-27891.md",
  "id": "GHSA-3pgc-xqg9-cfr6",
  "modified": "2026-05-07T19:32:14Z",
  "published": "2026-05-07T19:32:14Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/NeoRazorX/facturascripts/security/advisories/GHSA-3pgc-xqg9-cfr6"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/NeoRazorX/facturascripts"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "FacturaScripts Vulnerable to Remote Code Execution (RCE) via Zip Slip in Plugin Upload Mechanism"
}

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.

Detection rules are retrieved from Rulezet.

Action not permitted

CVE-2026-27891 (GCVE-0-2026-27891)

FKIE_CVE-2026-27891

GHSA-3PGC-XQG9-CFR6

Summary

Details

PoC

Impact

Tags

Sightings

Nomenclature