{"id":"CVE-2025-59028","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-59028","generatedAt":"2026-10-28T03:31:56.906Z","title":"Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins.","description":"When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.","published":"2026-03-27T09:16:19.000Z","lastModified":"2026-10-07T09:10:00.000Z","status":"Analyzed","sourceIdentifier":"security@open-xchange.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-20"],"affected":["dovecot/dovecot","open-xchange/dovecot"],"epss":{"score":0.00464,"percentile":0.40034,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json","tags":["Vendor Advisory"],"source":"security@open-xchange.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-59028","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."}