CVE-2021-20247
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.88%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.4 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 1.88% probability · 78th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-20, CWE-22
- Affected
- mbsync project/mbsync · fedoraproject/extra packages for enterprise linux · debian/debian linux · fedoraproject/fedora
- Source
- secalert@redhat.com
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1928963Issue Tracking, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/07/msg00001.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CAXQLCK35QGRCRENRTGKJO4VVZGUXUJJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GVDEBZQJMWDW5JFK4NTHH6DAFNAZTESW/
- https://security.gentoo.org/glsa/202208-15Third Party Advisory
- https://www.openwall.com/lists/oss-security/2021/02/22/1Exploit, Mailing List, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1928963Issue Tracking, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/07/msg00001.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CAXQLCK35QGRCRENRTGKJO4VVZGUXUJJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GVDEBZQJMWDW5JFK4NTHH6DAFNAZTESW/
- https://security.gentoo.org/glsa/202208-15Third Party Advisory
- https://www.openwall.com/lists/oss-security/2021/02/22/1Exploit, Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.