CVE-2021-20247 Information

Description

A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing ‘..’ path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Reference

https://bugzilla.redhat.com/show_bug.cgi?id=1928963 https://www.openwall.com/lists/oss-security/2021/02/22/1 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CAXQLCK35QGRCRENRTGKJO4VVZGUXUJJ/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GVDEBZQJMWDW5JFK4NTHH6DAFNAZTESW/

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.4