Vulnerabilities > CVE-2020-26820 - Unrestricted Upload of File with Dangerous Type vulnerability in SAP Netweaver Application Server Java
Attack vector
NETWORK Attack complexity
LOW Privileges required
HIGH Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
SAP NetWeaver AS JAVA, versions - 7.20, 7.30, 7.31, 7.40, 7.50, allows an attacker who is authenticated as an administrator to use the administrator console, to expose unauthenticated access to the file system and upload a malicious file. The attacker or another user can then use a separate mechanism to execute OS commands through the uploaded file leading to Privilege Escalation and completely compromise the confidentiality, integrity and availability of the server operating system and any application running on it.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 5 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Accessing Functionality Not Properly Constrained by ACLs In applications, particularly web applications, access to functionality is mitigated by the authorization framework, whose job it is to map ACLs to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application or can run queries for data that he is otherwise not supposed to.
- Privilege Abuse An adversary is able to exploit features of the target that should be reserved for privileged users or administrators but are exposed to use by lower or non-privileged accounts. Access to sensitive information and functionality must be controlled to ensure that only authorized users are able to access these resources. If access control mechanisms are absent or misconfigured, a user may be able to access resources that are intended only for higher level users. An adversary may be able to exploit this to utilize a less trusted account to gain information and perform activities reserved for more trusted accounts. This attack differs from privilege escalation and other privilege stealing attacks in that the adversary never actually escalates their privileges but instead is able to use a lesser degree of privilege to access resources that should be (but are not) reserved for higher privilege accounts. Likewise, the adversary does not exploit trust or subvert systems - all control functionality is working as configured but the configuration does not adequately protect sensitive resources at an appropriate level.