{"cve":"CVE-2021-29969","nvd":{"published":"2021-08-05T20:15:08.500","modified":"2026-06-17T03:48:31.790","status":"Modified","description":"If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses prior to the completion of the STARTTLS handshake, then Thunderbird didn't ignore the injected data. This could have resulted in Thunderbird showing incorrect information, for example the attacker could have tricked Thunderbird to show folders that didn't exist on the IMAP server. This vulnerability affects Thunderbird < 78.12.","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:N/A:N","score":5.9},"cwes":["CWE-552"],"references":["https://bugzilla.mozilla.org/show_bug.cgi?id=1682370","https://security.gentoo.org/glsa/202208-14","https://www.mozilla.org/security/advisories/mfsa2021-30/","https://bugzilla.mozilla.org/show_bug.cgi?id=1682370","https://security.gentoo.org/glsa/202208-14"],"products":["mozilla:thunderbird"],"source":"nvd","synced_at":"2026-10-19T21:21:13.713336758+00:00"},"epss":{"cve":"CVE-2021-29969","score":0.012,"percentile":0.68174,"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."]}