{"id":"GHSA-fr76-5637-w3g9","summary":"Sharp has Unrestricted File Upload via Client-Controlled Validation Rules","details":"### Summary \nThe `code16/sharp` Laravel admin panel package contains a vulnerability in its file upload endpoint that allows authenticated users to bypass all file type restrictions.\n\n### Details\nThe upload endpoint within the `ApiFormUploadController` accepts a client-controlled `validation_rule` parameter. This parameter is directly passed into the Laravel validator without sufficient server-side enforcement. By intercepting the request and sending `validation_rule[]=file`, an attacker can completely bypass all MIME type and file extension restrictions. The vulnerable code is located in `src/Http/Controllers/Api/ApiFormUploadController.php` at line 24.\n\n### Impact\nThis vulnerability leads to several critical security risks:\n\nAttackers can upload arbitrary files, including PHP webshells, to the server. For more details on the package, visit: https://github.com/code16/sharp\n\nMIME type and extension validation can be bypassed entirely via client-controlled rules. Review the CWE definition here: https://cwe.mitre.org/data/definitions/434.html\n\nIf the storage disk is configured to be publicly accessible, this can lead to Remote Code Execution (RCE). See the vendor repository: https://github.com/code16/sharp\n\n(Note: Under default configurations, executing uploaded PHP files directly is not possible unless a public disk configuration is in place.)\n\n### Patches\nThis issue has been addressed by removing the client-controlled validation rules and strictly defining upload rules server-side. The fix is available in pull request https://github.com/code16/sharp/pull/714.\n\n### Workarounds\n- Restrict Disk Access: Ensure that the storage disk used for Sharp uploads is strictly private. Under default configurations, an attacker cannot directly execute uploaded PHP files unless a public disk configuration is explicitly used. For more details on Laravel disk configurations, visit: https://laravel.com/docs/13.x/filesystem\n\n### Credits\nReported by [zaurgsynv](https://github.com/zaurgsynv).","aliases":["CVE-2026-33687"],"modified":"2026-03-27T21:49:57.246160Z","published":"2026-03-25T20:00:24Z","database_specific":{"github_reviewed_at":"2026-03-25T20:00:24Z","nvd_published_at":"2026-03-26T22:16:31Z","cwe_ids":["CWE-434"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/code16/sharp/security/advisories/GHSA-fr76-5637-w3g9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33687"},{"type":"WEB","url":"https://github.com/code16/sharp/pull/714"},{"type":"PACKAGE","url":"https://github.com/code16/sharp"},{"type":"WEB","url":"https://github.com/code16/sharp/releases/tag/v9.20.0"},{"type":"WEB","url":"https://laravel.com/docs/13.x/filesystem"}],"affected":[{"package":{"name":"code16/sharp","ecosystem":"Packagist","purl":"pkg:composer/code16/sharp"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.20.0"}]}],"versions":["7.0.0-alpha.1","7.27.0","7.7.2","v4.0-BETA1","v4.0-BETA2","v4.0-BETA3","v4.0-BETA4","v4.0-BETA5","v4.0-BETA6","v4.0.0","v4.0.1","v4.0.10","v4.0.11","v4.0.12","v4.0.13","v4.0.14","v4.0.15","v4.0.16","v4.0.17","v4.0.18","v4.0.19","v4.0.2","v4.0.20","v4.0.21","v4.0.3","v4.0.4","v4.0.5","v4.0.6","v4.0.7","v4.0.8","v4.0.9","v4.1.0","v4.1.1","v4.1.10","v4.1.11","v4.1.12","v4.1.13","v4.1.14","v4.1.15","v4.1.16","v4.1.17","v4.1.18","v4.1.19","v4.1.2","v4.1.20","v4.1.21","v4.1.22","v4.1.23","v4.1.24","v4.1.25","v4.1.3","v4.1.4","v4.1.5","v4.1.6","v4.1.7","v4.1.8","v4.1.9","v4.2.0","v4.2.1","v4.2.2","v4.2.3","v4.2.4","v4.2.5","v4.2.6","v5.0.0","v5.0.0-alpha.1","v5.0.0-alpha.10","v5.0.0-alpha.2","v5.0.0-alpha.3","v5.0.0-alpha.4","v5.0.0-alpha.5","v5.0.0-alpha.6","v5.0.0-alpha.7","v5.0.0-alpha.8","v5.0.0-alpha.9","v5.0.1","v5.1.0","v5.1.1","v5.1.2","v5.2.0","v5.3.0","v5.3.1","v5.3.2","v5.3.3","v5.3.4","v5.3.5","v5.4.0","v5.4.1","v5.4.2","v5.4.3","v5.4.4","v5.4.5","v5.4.6","v6.0.0","v6.0.0-alpha.1","v6.0.0-alpha.2","v6.0.0-alpha.3","v6.0.0-alpha.4","v6.0.0-alpha.5","v6.0.0-alpha.6","v6.0.0-alpha.7","v6.0.0-beta.1","v6.0.0-beta.2","v6.0.0-beta.3","v6.0.1","v6.1.0","v6.1.1","v6.1.2","v6.1.3","v6.1.4","v6.1.5","v6.2.0","v6.3.0","v6.3.1","v6.3.2","v6.3.3","v6.4.0","v6.4.1","v6.5.0","v6.5.1","v6.5.2","v6.5.3","v6.5.4","v6.5.5","v7.0.0","v7.0.0-beta.1","v7.0.0-beta.2","v7.0.0-beta.3","v7.0.0-beta.4","v7.0.0-beta.5","v7.0.0-beta.6","v7.0.1","v7.0.2","v7.1.0","v7.10.0","v7.11.0","v7.12.0","v7.13.0","v7.14.0","v7.15.0","v7.16.0","v7.17.0","v7.17.1","v7.17.2","v7.17.3","v7.18.0","v7.19.0","v7.19.1","v7.2.0","v7.2.1","v7.2.2","v7.2.3","v7.2.4","v7.2.5","v7.20.0","v7.21.0","v7.22.0","v7.23.0","v7.23.1","v7.23.2","v7.24.0","v7.24.1","v7.25.0","v7.25.1","v7.25.2","v7.26.0","v7.26.1","v7.26.2","v7.27.1","v7.28.0","v7.29.0","v7.29.1","v7.29.2","v7.29.3","v7.29.4","v7.29.5","v7.29.6","v7.29.7","v7.3.0","v7.30.0","v7.4.0","v7.5.0","v7.5.1","v7.5.2","v7.6.0","v7.7.0","v7.7.1","v7.8.0","v7.9.0","v8.0.0","v8.0.1","v8.0.2","v8.0.3","v8.0.4","v8.0.5","v8.0.6","v8.0.7","v8.1.0","v8.1.1","v8.1.2","v8.2.0","v8.2.1","v8.3.0","v8.3.1","v8.3.2","v8.3.3","v8.3.4","v8.3.5","v8.3.6","v8.3.7","v8.4.0","v8.4.1","v8.4.2","v8.4.3","v8.4.4","v8.5.0","v8.6.0","v8.6.1","v9.0.0","v9.0.0-alpha.1","v9.0.0-alpha.2","v9.0.0-beta.1","v9.0.0-beta.10","v9.0.0-beta.11","v9.0.0-beta.12","v9.0.0-beta.13","v9.0.0-beta.14","v9.0.0-beta.15","v9.0.0-beta.16","v9.0.0-beta.17","v9.0.0-beta.2","v9.0.0-beta.3","v9.0.0-beta.4","v9.0.0-beta.5","v9.0.0-beta.6","v9.0.0-beta.7","v9.0.0-beta.8","v9.0.0-beta.9","v9.0.1","v9.0.2","v9.0.3","v9.0.4","v9.0.5","v9.0.6","v9.0.7","v9.0.8","v9.0.9","v9.1.0","v9.1.1","v9.1.2","v9.10.0","v9.10.1","v9.10.2","v9.11.0","v9.11.1","v9.12.0","v9.13.0","v9.13.1","v9.14.0","v9.14.1","v9.14.2","v9.14.3","v9.14.4","v9.15.0","v9.15.1","v9.16.0","v9.16.1","v9.17.0","v9.17.1","v9.18.0","v9.19.0","v9.19.1","v9.19.2","v9.19.3","v9.2.0","v9.2.1","v9.2.2","v9.2.3","v9.2.4","v9.2.5","v9.2.6","v9.2.7","v9.2.8","v9.3.0","v9.3.1","v9.3.2","v9.3.3","v9.3.4","v9.3.5","v9.3.6","v9.3.7","v9.4.0","v9.4.1","v9.5.0","v9.5.1","v9.5.2","v9.6.0","v9.6.1","v9.6.2","v9.6.3","v9.6.4","v9.6.5","v9.6.6","v9.7.0","v9.7.1","v9.7.2","v9.7.3","v9.8.0","v9.8.1","v9.9.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-fr76-5637-w3g9/GHSA-fr76-5637-w3g9.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}