What is the CVSS score of CVE-2021-20247?

CVE-2021-20247 has a CVSS 3.1 base score of 7.4 (High). CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N. EPSS exploitation probability: 1.9%.

Is there a public PoC exploit available for CVE-2021-20247?

Yes, a public proof-of-concept exploit is available for CVE-2021-20247. Prioritise patching immediately. EPSS: 1.9%.

Mbsync CVE-2021-20247

HIGH

Improper Input Validation (CWE-20)

2021-02-23 secalert@redhat.com

Information Disclosure Mbsync Extra Packages For Enterprise Linux Debian Linux Fedora

7.4

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.4 HIGH

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Lifecycle Timeline

CVE Published

Feb 23, 2021 - 19:15 nvd

HIGH 7.4

DescriptionNVD

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.

AnalysisAI

A flaw was found in mbsync before v1.3.5 and v1.4.1. Rated high severity (CVSS 7.4), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-20. 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 products include: Mbsync Project Mbsync, Fedoraproject Extra Packages For Enterprise Linux, Debian Debian Linux, Fedoraproject Fedora.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.