HIGH · 7.4

CVE-2021-20247

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 mailbo...

Vulnerability 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 Score

7.4

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE

Affected Products

VendorProductVersions
Mbsync ProjectMbsync< 1.3.5
FedoraprojectExtra Packages For Enterprise Linux8.0
DebianDebian Linux9.0
FedoraprojectFedora32

Related Weaknesses (CWE)

References

FAQ

What is CVE-2021-20247?

CVE-2021-20247 is a vulnerability with a CVSS score of 7.4 (HIGH). 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 mailbo...

How severe is CVE-2021-20247?

CVE-2021-20247 has been rated HIGH with a CVSS base score of 7.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-20247?

Check the references section above for vendor advisories and patch information. Affected products include: Mbsync Project Mbsync, Fedoraproject Extra Packages For Enterprise Linux, Debian Debian Linux, Fedoraproject Fedora.