{"cve":"CVE-2021-44143","nvd":{"published":"2021-11-22T20:15:18.223","modified":"2026-06-17T04:11:56.860","status":"Modified","description":"A flaw was found in mbsync in isync 1.4.0 through 1.4.3. Due to an unchecked condition, a malicious or compromised IMAP server could use a crafted mail message that lacks headers (i.e., one that starts with an empty line) to provoke a heap overflow, which could conceivably be exploited for remote code execution.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-787"],"references":["http://www.openwall.com/lists/oss-security/2021/12/03/2","https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=999804","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CYZ2GNB4ZO2T27D2XNUWMCS3THZYSJQU/","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCBSY7OZ57XNC6ZYXF6WU5KBSWITZVDX/","https://security.gentoo.org/glsa/202208-15"],"products":["debian:debian_linux","fedoraproject:fedora","isync_project:isync"],"source":"nvd","synced_at":"2026-10-19T21:25:41.256909649+00:00"},"epss":{"cve":"CVE-2021-44143","score":0.03783,"percentile":0.89958,"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."]}