SB2021081609 - Multiple vulnerabilities in Contao

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-37627)

The vulnerability allows a remote administrator to escalate privileges on the system.

The vulnerability exists due to application does not properly impose security restrictions in the form generator, which leads to security restrictions bypass and privilege escalation.

2) Code Injection (CVE-ID: CVE-2021-37626)

The vulnerability allows a remote local to execute arbitrary code on the target system.

The vulnerability exists due to improper input validation. A remote administrator can load PHP files and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

3) Cross-site scripting (CVE-ID: CVE-2021-35955)

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data. A remote authenticated attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Remediation

Install update from vendor's website.

References

• https://github.com/contao/contao/security/advisories/GHSA-hq5m-mqmx-fw6m
• https://contao.org/en/security-advisories/privilege-escalation-with-the-form-generator.html
• https://contao.org/en/security-advisories/php-file-inclusion-via-insert-tags.html
• https://github.com/contao/contao/security/advisories/GHSA-r6mv-ppjc-4hgr
• https://contao.org/en/news/contao-4-9-16-and-4-11-5-are-available.html
• https://github.com/contao/contao/security/advisories/GHSA-hr3h-x6gq-rqcp