SB2021061109 - Multiple vulnerabilities in SilverStripe Framework

Description

This security bulletin contains information about 2 vulnerabilities.

1) Input validation error (CVE-ID: CVE-2020-26138)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

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

The vulnerability exists due to a FormField with square brackets in the field name skips validation. 

2) XML External Entity injection (CVE-ID: CVE-2020-25817)

CWE-ID: CWE-611 - Improper Restriction of XML External Entity Reference ('XXE')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

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

The vulnerability exists due to insufficient validation of user-supplied XML input in CSSContentParser. A remote administrator can pass a specially crafted XML code to the affected application and view contents of arbitrary files on the system or initiate requests to external systems.

Successful exploitation of the vulnerability may allow an attacker to view contents of arbitrary file on the server or perform network scanning of internal and external infrastructure.

Remediation

Install update from vendor's website.

References

• https://www.silverstripe.org/download/security-releases/
• https://www.silverstripe.org/blog/tag/release
• https://forum.silverstripe.org/c/releases
• https://www.silverstripe.org/download/security-releases/cve-2020-26138
• https://www.silverstripe.org/download/security-releases/cve-2020-25817