{"cve":"CVE-2021-24171","nvd":{"published":"2021-04-05T19:15:15.857","modified":"2026-06-17T03:39:30.930","status":"Modified","description":"The WooCommerce Upload Files WordPress plugin before 59.4 ran a single sanitization pass to remove blocked extensions such as .php. It was possible to bypass this and upload a file with a PHP extension by embedding a \"blocked\" extension within another \"blocked\" extension in the \"wcuf_file_name\" parameter. It was also possible to perform a double extension attack and upload files to a different location via path traversal using the \"wcuf_current_upload_session_id\" parameter.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-434"],"references":["https://wpscan.com/vulnerability/ed4288a1-f7e4-455f-b765-5ac343f87194","https://www.wordfence.com/blog/2021/03/critical-vulnerability-patched-in-woocommerce-upload-files/","https://wpscan.com/vulnerability/ed4288a1-f7e4-455f-b765-5ac343f87194","https://www.wordfence.com/blog/2021/03/critical-vulnerability-patched-in-woocommerce-upload-files/"],"products":["vanquish:woocommerce_upload_files"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2021-24171","score":0.01899,"percentile":0.79662,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}