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…

PriorityP346high7.4CVSS 3.1

AVNACHPRNUINSUCHIHAN

EPSS

1.88%

76.8th percentile

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.

Affected

13 ranges

Vendor	Product	Version range	Fixed in
debian	debian_linux	—	—
debian	isync	< isync 1.3.0-2.1 (bookworm)	isync 1.3.0-2.1 (bookworm)
fedoraproject	extra_packages_for_enterprise_linux	—	—
fedoraproject	fedora	—	—
fedoraproject	fedora	—	—
isync	mbsync	—	—
isync	mbsync	—	—
isync_project	isync	>= 0 < 1.3.0-2.1	1.3.0-2.1
isync_project	isync	>= 0 < 1.3.0-2.1	1.3.0-2.1
isync_project	isync	>= 0 < 1.3.0-2.1	1.3.0-2.1
isync_project	isync	>= 0 < 1.3.0-2.1	1.3.0-2.1
mbsync_project	mbsync	< 1.3.5	1.3.5
mbsync_project	mbsync	>= 1.4.0 < 1.4.1	1.4.1

CVSS provenance

nvdv3.17.4HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

nvdv2.05.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:N

osv7.4HIGH

vendor_debian7.4HIGH

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