{"cve":"CVE-2026-75833","nvd":{"published":"2026-08-18T12:19:33.370","modified":"2026-10-22T22:10:00.250","status":"Deferred","description":"The Grav API plugin (getgrav/grav-plugin-api, bundled with Grav 2.0's admin-next/API stack) before version 1.0.14 contains an open redirect weakness in SsoController::sanitizeReturnTo(). The function rejects a literal '//' prefix but does not account for browsers normalizing backslashes to slashes in special (http/https) schemes, so a returnTo value such as '/\\evil.com' passes the guard and is later resolved by the browser as the protocol-relative URL '//evil.com'. Following a legitimate OAuth login flow, an attacker-supplied returnTo parameter could redirect an authenticated victim to an attacker-controlled site for post-login phishing. Full browser-side exploitability depends on the admin-next SPA's client-side oauth-callback handler and was not independently verified by the reporter.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":8.6},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","score":4.2},"cwes":["CWE-601"],"references":["https://github.com/getgrav/grav/security/advisories/GHSA-x72c-4jc4-8rh6","https://www.vulncheck.com/advisories/grav-api-plugin-open-redirect-via-backslash-bypass"],"products":[],"source":"nvd","synced_at":"2026-10-23T16:39:26.291718493+00:00"},"epss":{"cve":"CVE-2026-75833","score":0.00219,"percentile":0.12237,"date":"2026-10-25"},"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."]}