CVE-2023-23943: Blind SSRF via server URL input in the Nextcloud Mail app

Published Feb 6, 2023
·
Updated

Nextcloud mail is an email app for the nextcloud home server platform. In affected versions the SMTP, IMAP and Sieve host fields allowed to scan for internal services and servers reachable from within the local network of the Nextcloud Server. It is recommended that the Nextcloud Maill app is upgraded to 1.15.0 or 2.2.2. The only known workaround for this issue is to completely disable the nextcloud mail app.

Affected Software

2 affected components
Nextcloud Mail<1.15.0
Nextcloud Mail>=2.2.0<2.2.2

Event History

Feb 6, 2023
CVE Published
via MITRE·08:18 PM
Data Sourced
via MITRE·08:18 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-23943?

CVE-2023-23943 is a vulnerability in Nextcloud Mail, an email app for the Nextcloud home server platform, that allows scanning for internal services and servers reachable from within the local network of the Nextcloud Server.

2

What is the severity of CVE-2023-23943?

The severity of CVE-2023-23943 is medium with a CVSS score of 4.3.

3

How does CVE-2023-23943 affect Nextcloud Mail?

CVE-2023-23943 affects Nextcloud Mail by allowing the scanning of internal services and servers within the local network of the Nextcloud Server.

4

How can I fix CVE-2023-23943?

To fix CVE-2023-23943, it is recommended to upgrade the Nextcloud Mail app to a version higher than 1.15.0 or between 2.2.0 and 2.2.2.

5

Where can I find more information about CVE-2023-23943?

You can find more information about CVE-2023-23943 in the references provided: [GitHub Pull Request](https://github.com/nextcloud/mail/pull/7796), [Nextcloud Security Advisories](https://github.com/nextcloud/security-advisories/security/advisories/GHSA-8gcx-r739-9pf6), [HackerOne Report](https://hackerone.com/reports/1736390).

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