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SMTP Command Injection in iCalendar Attachments to emails via newlines

Moderate
nickvergessen published GHSA-264h-3v4w-6xh2 Jul 4, 2022

Package

Server (Nextcloud)

Affected versions

< 22.2.8, < 23.0.5, < 24.0.1

Patched versions

22.2.8, 23.0.5, 24.0.1
Server (Nextcloud Enterprise)
<19.0.13.7, <20.0.14.6, <21.0.9.5, <22.2.8, <23.0.5
19.0.13.7, 20.0.14.6, 21.0.9.5, 22.2.8, 23.0.5

Description

Impact

The impact varies based on which commands are supported by the backend SMTP server. However, the main risk here is that the attacker can then hijack an already-authenticated SMTP session and run arbitrary SMTP commands as the email user, such as sending emails to other users, changing the FROM user, and so on. As before, this depends on the configuration of the server itself, but newlines should be sanitized to mitigate such arbitrary SMTP command injection.

Patches

It is recommended that the Nextcloud Server is upgraded to 22.2.8 , 23.0.5 or 24.0.1.
It is recommended that the Nextcloud Enterprise Server is upgraded to 19.0.13.7, 20.0.14.6, 21.0.9.5, 22.2.8 or 23.0.5.

Workarounds

No workaround available

References

For more information

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Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N

CVE ID

CVE-2022-31014

Weaknesses

Credits