CVE-2021-3657

Publication date 18 February 2022

Last updated 11 July 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

9.8 · Critical

Score breakdown

Description

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 remote code execution.

Status

Package Ubuntu Release Status
isync 26.04 LTS resolute
Vulnerable
25.10 questing
Vulnerable
25.04 plucky Ignored end of life, was needed
24.10 oracular Ignored end of life, was needed
24.04 LTS noble
Vulnerable
23.10 mantic Ignored end of life, was needed
23.04 lunar Ignored end of life, was needed
22.10 kinetic Ignored end of life, was needed
22.04 LTS jammy
Vulnerable
21.10 impish Ignored end of life
21.04 hirsute Ignored end of life
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial Ignored end of standard support
14.04 LTS trusty Ignored end of standard support

Severity score breakdown

Parameter Value
Base score 9.8 · Critical
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Other references

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