{"id":"CVE-2026-13163","summary":"Lack of input validation in Mailerup input parameter leads to Open Redirect","details":"Open redirect vulnerability (CWE-601) in the _safe_redirect function of the click-tracking endpoint (/c/\u003ctoken\u003e/) in Mailerup \u003c1.0.0 on all platforms allows remote unauthenticated attackers to redirect victims to arbitrary external sites and conduct phishing attacks via a crafted u query parameter, because the URL scheme is validated (blocking javascript: and data:) but the destination host is not restricted to an allowlist, and a signing.BadSignature exception is silently caught so a valid signed token is not required.","modified":"2026-07-15T01:48:52.335191513Z","published":"2026-06-24T12:49:05.227Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/13xxx/CVE-2026-13163.json","unresolved_ranges":[{"extracted_events":[{"fixed":"1.0.1"}],"source":"AFFECTED_FIELD"},{"source":"CPE_FIELD","extracted_events":[{"fixed":"1.0.1"}]}],"cna_assigner":"Secur0","cwe_ids":["CWE-601"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/13xxx/CVE-2026-13163.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-13163"},{"type":"FIX","url":"https://github.com/Maalfer/mailerup/commit/99eb6d4586134bf3f4422093fbf47d6794ef0ee5"},{"type":"PACKAGE","url":"https://github.com/Maalfer/mailerup"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/maalfer/mailerup","events":[{"introduced":"0"},{"fixed":"99eb6d4586134bf3f4422093fbf47d6794ef0ee5"}],"database_specific":{"source":"REFERENCES"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-13163.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N"}]}