Security advisory

{
  "id": "d013874496f40a802f2e0187eb32b2ff859efc50df09cf834453e1fef26bf89b",
  "url": "https://osv.dev/vulnerability/CVE-2020-5256",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-5256",
    "summary": "BookStack before version 0.25.5 has a vulnerability where a user could upload PHP files through image upload functions, which would allow them to execute code on the host system remotely. They would then have the permissions of the PHP process. This most impacts scenarios where non-trusted users are given permission to upload images in any area of the application. The issue was addressed in a series of patches in versions 0.25.3, 0.25.4 and 0.25.5. Users should upgrade to at least v0.25.5 to avoid this vulnerability.",
    "evidence": "osv:CVE-2020-5256",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2020-5256",
      "aliases": [
        "CVE-2020-5256",
        "GHSA-g9rq-x4fj-f5hx"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/bookstackapp/bookstack",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "119b539586f5ab13bca23273df0afd58c5aaa3b5"
                },
                {
                  "fixed": "c3e74219c414048707580488d390b9f478b216f5"
                },
                {
                  "fixed": "934512d09cac243787170d1ed142d4221e67275b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:bookstackapp:bookstack:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.25.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "119b539586f5ab13bca23273df0afd58c5aaa3b5"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.25.3"
                  },
                  {
                    "range": [
                      {
                        "fixed": "c3e74219c414048707580488d390b9f478b216f5"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.25.4"
                  },
                  {
                    "range": [
                      {
                        "fixed": "934512d09cac243787170d1ed142d4221e67275b"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.25.5"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.25.2",
            "v0.25.1",
            "v0.25.0",
            "v0.24.3",
            "v0.24.2",
            "v0.24.1",
            "v0.24.0",
            "v0.23.2",
            "v0.23.1",
            "v0.23.0",
            "v0.22.0",
            "v0.21.0",
            "v0.20.3",
            "v0.20.2",
            "v0.20.1",
            "v0.20.0",
            "v0.19.0",
            "v0.18.5",
            "v0.18.4",
            "v0.18.3",
            "v0.18.2",
            "v0.18.1",
            "v0.18.0",
            "v0.17.4",
            "v0.17.3",
            "v0.17.2",
            "v0.17.1",
            "v0.17.0",
            "v0.16.3",
            "v0.16.2",
            "v0.16.1",
            "v0.16.0",
            "v0.15.3",
            "v0.15.2",
            "v0.15.1",
            "v0.15.0",
            "v0.14.3",
            "v0.14.2",
            "v0.14.1",
            "v0.14.0",
            "v0.13.1",
            "v0.13.0",
            "v0.12.2",
            "v0.12.1",
            "v0.12.0",
            "v0.11.2",
            "v0.11.1",
            "v0.11.0",
            "v0.10.0",
            "v0.9.3",
            "v0.9.2",
            "v0.9.1",
            "v0.9.0",
            "v0.8.2",
            "v0.8.1",
            "v0.8.0",
            "v0.7.6",
            "v0.7.5",
            "v0.7.4",
            "v0.7.3",
            "0.7.2",
            "v.0.7.1",
            "v0.7.0",
            "v0.6.3",
            "v0.6.2",
            "v0.6.1",
            "v0.6.0",
            "v0.5.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-5256.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:22.501682794Z",
      "provider": "osv",
      "references": [
        "https://github.com/BookStackApp/BookStack/releases/tag/v0.25.3",
        "https://github.com/BookStackApp/BookStack/releases/tag/v0.25.4",
        "https://github.com/BookStackApp/BookStack/releases/tag/v0.25.5",
        "https://github.com/BookStackApp/BookStack/security/advisories/GHSA-g9rq-x4fj-f5hx"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-5256",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 385233,
  "published_at": "2020-03-09T16:15:15.75+00:00"
}