{"cve":"CVE-2021-38084","nvd":{"published":"2021-08-03T22:15:09.310","modified":"2026-06-17T04:01:26.043","status":"Modified","description":"An issue was discovered in the POP3 component of Courier Mail Server before 1.1.5. Meddler-in-the-middle attackers can pipeline commands after the POP3 STLS command, injecting plaintext commands into an encrypted user session.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-74"],"references":["https://sourceforge.net/p/courier/mailman/courier-imap/thread/cone.1382574216.483027.8082.1000%40monster.email-scan.com/#msg31555583","https://sourceforge.net/p/courier/mailman/message/37329216/","https://sourceforge.net/p/courier/mailman/courier-imap/thread/cone.1382574216.483027.8082.1000%40monster.email-scan.com/#msg31555583","https://sourceforge.net/p/courier/mailman/message/37329216/"],"products":["courier-mta:courier_mail_server"],"source":"nvd","synced_at":"2026-10-19T21:21:13.713336758+00:00"},"epss":{"cve":"CVE-2021-38084","score":0.01369,"percentile":0.7189,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}