https://patchthecve.com/CVEs with upgrade or downgrade fix stepshttps://patchthecve.com/cve/CVE-2021-3657.htmlhttps://patchthecve.com/cve/CVE-2021-3657.htmlWed, 17 Jun 2026 04:05:31 +0000CRITICAL 9.8: A flaw was found in mbsync versions prior to 1.4.4. Due to inadequate handling of extremely large (>=2GiB) IMAP literals, malicious or compromised IMAP servers, and hypothetically even external email senders, could cause several different buffer overflows, which could conceivably be exploited for rehttps://patchthecve.com/cve/CVE-2021-3578.htmlhttps://patchthecve.com/cve/CVE-2021-3578.htmlWed, 17 Jun 2026 04:05:22 +0000HIGH 7.8: A flaw was found in mbsync before v1.3.6 and v1.4.2, where an unchecked pointer cast allows a malicious or compromised server to write an arbitrary integer value past the end of a heap-allocated structure by issuing an unexpected APPENDUID response. This could be plausibly exploited for remote code https://patchthecve.com/cve/CVE-2021-44143.htmlhttps://patchthecve.com/cve/CVE-2021-44143.htmlWed, 17 Jun 2026 04:11:56 +0000CRITICAL 9.8: 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 co