{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-13163","assignerOrgId":"4daa8cea-433a-44bd-9456-53b127fc289a","state":"PUBLISHED","assignerShortName":"Secur0","dateReserved":"2026-06-24T12:44:34.692Z","datePublished":"2026-06-24T12:49:05.227Z","dateUpdated":"2026-06-24T13:07:07.003Z"},"containers":{"cna":{"providerMetadata":{"orgId":"4daa8cea-433a-44bd-9456-53b127fc289a","shortName":"Secur0","dateUpdated":"2026-06-24T12:49:05.227Z"},"title":"Lack of input validation in Mailerup input parameter leads to Open Redirect","datePublic":"2026-06-24T12:40:00.000Z","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-601","description":"CWE-601 URL redirection to untrusted site ('open redirect')","type":"CWE"}]}],"affected":[{"vendor":"Mailerup","product":"Mailerup","repo":"https://github.com/Maalfer/mailerup","versions":[{"status":"affected","version":"0","lessThan":"1.0.1","versionType":"custom"}],"defaultStatus":"unaffected"}],"cpeApplicability":[{"operator":"OR","nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:mailerup:mailerup:*:*:*:*:*:*:*:*","versionStartIncluding":"0","versionEndExcluding":"1.0.1"}]}]}],"descriptions":[{"lang":"en","value":"Open redirect vulnerability (CWE-601) in the _safe_redirect function of the click-tracking endpoint (/c/<token>/) in Mailerup <1.0.0 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.","supportingMedia":[{"type":"text/html","base64":false,"value":"Open redirect vulnerability (CWE-601) in the <code>_safe_redirect</code> function of the click-tracking endpoint (<code>/c/&lt;token&gt;/</code>) in <code>Mailerup &lt;1.0.0</code>&nbsp;on all platforms allows remote unauthenticated attackers to redirect victims to arbitrary external sites and conduct phishing attacks via a crafted <code>u</code>&nbsp;query parameter, because the URL scheme is validated (blocking <code>javascript:</code> and <code>data:</code>) but the destination host is not restricted to an allowlist, and a <code>signing.BadSignature</code> exception is silently caught so a valid signed token is not required."}]}],"references":[{"url":"https://github.com/Maalfer/mailerup/commit/99eb6d4586134bf3f4422093fbf47d6794ef0ee5","tags":["patch"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","subIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":5.3,"vectorString":"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"}}],"solutions":[{"lang":"en","value":"Upgrade to version 1.0.1 or higher.","supportingMedia":[{"type":"text/html","base64":false,"value":"Upgrade to version 1.0.1 or higher."}]}],"credits":[{"lang":"en","value":"Dario Rivas Quero from Secur0 security team","type":"finder"},{"lang":"en","value":"Cristian Fernandez Cornejo from Secur0 security team","type":"finder"},{"lang":"en","value":"Mario Alvarez Fernandez","type":"remediation developer"},{"lang":"en","value":"Xoan M. Otero Jorge","type":"analyst"},{"lang":"en","value":"Secur0 CNA","type":"coordinator"}],"source":{"discovery":"INTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.2"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-24T13:06:55.947222Z","id":"CVE-2026-13163","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-24T13:07:07.003Z"}}]}}