SB2021090707 - Multiple vulnerabilities in Nextcloud Server

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Inclusion of Sensitive Information in Log Files (CVE-ID: CVE-2021-32801)

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to software stores sensitive information into log files. A remote attacker can read the log files and gain access to sensitive data.

2) Information disclosure (CVE-ID: CVE-2021-32766)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output within the Nextcloud Text application. A remote attacker can gain unauthorized access to sensitive information on the system.

3) Improper Authentication (CVE-ID: CVE-2021-32800)

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in when processing authentication requests. A remote authenticated attacker can bypass Two Factor Authentication and gain access to an account.

4) Inclusion of Functionality from Untrusted Control Sphere (CVE-ID: CVE-2021-32802)

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to preview generation used third-party library not suited for user-generated content. A remote attacker can execute arbitrary code on the target system.

Remediation

Install update from vendor's website.

References

• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-mcpf-v65v-359h/
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-gcf3-3wmc-88jr/
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-gv5w-8q25-785v/
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7/