Canto <= 3.1.1 - Missing Authorization to Unauthenticated File Upload
Summary
| CVE | CVE-2026-3335 |
|---|---|
| State | PUBLISHED |
| Assigner | Wordfence |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-21 04:17:20 UTC |
| Updated | 2026-04-24 16:27:44 UTC |
| Description | The Canto plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 3.1.1 via the `/wp-content/plugins/canto/includes/lib/copy-media.php` file. This is due to the file being directly accessible without any authentication, authorization, or nonce checks, and the `fbc_flight_domain` and `fbc_app_api` URL components being accepted as user-supplied POST parameters rather than read from admin-configured options. Since the attacker controls both the destination server and the `fbc_app_token` value, the entire fetch-and-upload chain is attacker-controlled — the server never contacts Canto's legitimate API, and the uploaded file originates entirely from the attacker's infrastructure. This makes it possible for unauthenticated attackers to upload arbitrary files (constrained to WordPress-allowed MIME types) to the WordPress uploads directory. Additional endpoints (`detail.php`, `download.php`, `get.php`, `tree.php`) are also directly accessible without authentication and make requests using a user-supplied `app_api` parameter combined with an admin-configured subdomain. |
Risk And Classification
Primary CVSS: v3.1 5.3 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS: 0.002310000 probability, percentile 0.458650000 (date 2026-04-26)
Problem Types: CWE-862 | CWE-862 CWE-862 Missing Authorization
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 5.3 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| 3.1 | CNA | DECLARED | 5.3 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Flightbycanto | Canto | affected 3.1.1 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| plugins.trac.wordpress.org/browser/canto/tags/3.1.1/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/canto/tags/3.1.1/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/canto/trunk/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| www.wordfence.com/threat-intel/vulnerabilities/id/0777f759-6980-4572-a866-0210b... | [email protected] | www.wordfence.com | |
| plugins.trac.wordpress.org/browser/canto/trunk/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/canto/trunk/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| plugins.trac.wordpress.org/browser/canto/tags/3.1.1/includes/lib/copy-media.php | [email protected] | plugins.trac.wordpress.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: heygork (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-03-20T15:13:52.000Z | Disclosed |
There are currently no legacy QID mappings associated with this CVE.