{"id":"CVE-2026-55840","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-55840","generatedAt":"2026-10-28T00:51:52.244Z","title":"An attacker can supply an absolute URL whose hostname begins with the legitimate hostname, causing URI.resolve() to retain the attacker URL and the prefix check to accept it.","description":"Scoold is a Q&A and a knowledge sharing platform for teams. Prior to 1.69.1, the getBackToUrl() method in src/main/java/com/erudika/scoold/utils/HttpUtils.java validates the backto and returnto parameters with Strings.CI.startsWith against the configured server URL. An attacker can supply an absolute URL whose hostname begins with the legitimate hostname, causing URI.resolve() to retain the attacker URL and the prefix check to accept it. A victim who follows the crafted sign-in link can be redirected to an attacker-controlled domain after authentication, enabling phishing and possible credential or token theft. This issue is fixed in version 1.69.1.","published":"2026-10-15T19:17:41.000Z","lastModified":"2026-10-15T21:17:14.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.4,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"},"cwe":["CWE-601"],"affected":[],"epss":{"score":0.00264,"percentile":0.1806,"date":"2026-10-26","history":[{"date":"2026-10-16","score":0.00264,"percentile":0.17006}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.26%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-15T19:17:41.000Z","detail":{"score":"5.4","severity":"MEDIUM","publishedAt":"2026-10-15T19:17:40.823Z"},"summary":"New CVE, medium severity (CVSS 5.4)."}],"references":[{"url":"https://github.com/Erudika/scoold/commit/9d61f6fe15d4f9f6262812ba7fea43be8d5bb745","source":"security-advisories@github.com"},{"url":"https://github.com/Erudika/scoold/releases/tag/1.69.1","source":"security-advisories@github.com"},{"url":"https://github.com/Erudika/scoold/security/advisories/GHSA-85fm-6f2v-74pq","source":"security-advisories@github.com"},{"url":"https://github.com/Erudika/scoold/security/advisories/GHSA-85fm-6f2v-74pq","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55840","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}