{"id":"PYSEC-2026-109","details":"pretalx is a conference planning tool. Prior to 2026.1.0, an unauthenticated attacker can send arbitrary HTML-rendered emails from a pretalx instance's configured sender address by embedding malformed HTML or markdown link syntax in a user-controlled template placeholder such as the account display name. The most direct vector is the password-reset flow: the attacker registers an account with a malicious name, enters the victim's email address, and triggers a password reset. The resulting email is delivered from the event's legitimate sender address and passes SPF/DKIM/DMARC validation, making it a ready-made phishing vector. This vulnerability is fixed in 2026.1.0.","aliases":["CVE-2026-41426","GHSA-jm8c-9f3j-4378"],"modified":"2026-05-20T09:19:11.385949Z","published":"2026-04-24T20:16:27.247Z","references":[{"type":"ADVISORY","url":"https://github.com/pretalx/pretalx/security/advisories/GHSA-jm8c-9f3j-4378"}],"affected":[{"package":{"name":"pretalx","ecosystem":"PyPI","purl":"pkg:pypi/pretalx"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2026.1.0"}]}],"versions":["0.1.0","0.2.0.post1","0.2.1.post1","0.2.2","0.3.0","0.3.1","0.4.0","0.4.1","0.5.0","0.6.0","0.6.1","0.7.0","0.7.1","0.8.0","0.9.0","1.0.0","1.0.1","1.0.2","1.0.3","1.0.4","1.1.0","1.1.1","1.1.2","2.0.0","2.1.0","2.1.1","2.2.0","2.3.0","2.3.1","2.3.2","2023.1.0","2023.1.1","2023.1.2","2023.1.3","2024.1.0","2024.2.0","2024.2.1","2024.3.0","2024.3.1","2025.1.0","2025.2.0","2025.2.1","2025.2.2"],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/pretalx/PYSEC-2026-109.yaml"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}