{"cve":"CVE-2020-26768","nvd":{"published":"2021-01-07T13:15:11.623","modified":"2026-06-17T03:08:20.770","status":"Modified","description":"Formstone <=1.4.16 is vulnerable to a Reflected Cross-Site Scripting (XSS) vulnerability caused by improper validation of user supplied input in the upload-target.php and upload-chunked.php files. A remote attacker could exploit this vulnerability using a specially crafted URL to execute a script in a victim's Web browser within the security context of the hosting Web site once the URL is clicked or visited. An attacker could use this vulnerability to steal the victim's cookie-based authentication credentials, force malware execution, user redirection and others.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://github.com/Formstone/Formstone/issues/286","https://github.com/Formstone/Formstone/issues/286"],"products":["formstone:formstone"],"source":"nvd","synced_at":"2026-10-19T21:12:09.559580076+00:00"},"epss":{"cve":"CVE-2020-26768","score":0.01277,"percentile":0.69972,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-wc29-h54q-q8qx","url":"https://osv.dev/vulnerability/GHSA-wc29-h54q-q8qx","summary":"Formstone Vulnerable to Reflected XSS","modified":"2024-04-01T22:27:14.842993Z","packages":[{"ecosystem":"npm","name":"formstone","purl":"pkg:npm/formstone","ranges":["<1.4.17"],"fixed":["1.4.17"]}]}],"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."]}