{"id":"CVE-2026-55875","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-55875","generatedAt":"2026-10-28T03:28:54.124Z","title":"Prior to 2.2.60, any authenticated user can submit an arbitrary URL to POST /feed/externalcalendars/, where helium/feed/services/icalexternalcalendarservice.py uses validate_url to check only URL syntax before passing the value to…","description":"Helium is a free online student planner for classes, homework, grades, and notes. Prior to 2.2.60, any authenticated user can submit an arbitrary URL to POST /feed/externalcalendars/, where helium/feed/services/icalexternalcalendarservice.py uses validate_url to check only URL syntax before passing the value to urllib.request.urlopen, and fetch_ical_conditional periodically refetches the stored URL. The server can therefore issue requests to attacker-selected external or internal hosts, while distinct responses, including an uncaught http.client.RemoteDisconnected condition for non-HTTP services, reveal internal host and port reachability. The supported impact is forced outbound requests and internal service reconnaissance; the advisory does not demonstrate secret retrieval because the relevant ECS credentials path is task-specific and unpredictable. This issue is fixed in version 2.2.60.","published":"2026-10-15T18:17:28.000Z","lastModified":"2026-10-16T20:04:30.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"},"cwe":["CWE-918"],"affected":[],"epss":{"score":0.0021,"percentile":0.11163,"date":"2026-10-26","history":[{"date":"2026-10-16","score":0.0021,"percentile":0.10536}]},"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 (0.21%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-15T18:17:28.000Z","detail":{"score":"4.3","severity":"MEDIUM","publishedAt":"2026-10-15T18:17:28.130Z"},"summary":"New CVE, medium severity (CVSS 4.3)."}],"references":[{"url":"https://github.com/HeliumEdu/platform/commit/f0de5c985c701942758b805a3d11dfb008a6af88","source":"security-advisories@github.com"},{"url":"https://github.com/HeliumEdu/platform/security/advisories/GHSA-2f83-94pv-v3f5","source":"security-advisories@github.com"},{"url":"https://github.com/HeliumEdu/platform/security/advisories/GHSA-2f83-94pv-v3f5","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55875","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."}