Critical severity · published Apr 11, 2022
CVE-2022-24838
Nextcloud Calendar is a calendar application for the nextcloud framework
9.8
CVSS
33%
EPSS
No
On KEV
Description
Nextcloud Calendar is a calendar application for the nextcloud framework. SMTP Command Injection in Appointment Emails via Newlines: as newlines and special characters are not sanitized in the email value in the JSON request, a malicious attacker can inject newlines to break out of the `RCPT TO:<BOOKING USER'S EMAIL> ` SMTP command and begin injecting arbitrary SMTP commands. It is recommended that Calendar is upgraded to 3.2.2. There are no workaround available.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)33.0% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CA
Calendar · Nextcloud
before 3.2.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2022-24838
CVE.org
https://www.cve.org/CVERecord?id=CVE-2022-24838
Patch
https://github.com/nextcloud/calendar/commit/7b70edfb8a0fcf0926f613ababcbd56c6ecd9f35
Patch
https://github.com/nextcloud/calendar/pull/4073
Third Party Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-8xv5-4855-24qf
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