Vulnerabilities > CVE-2016-9553 - Command Injection vulnerability in Sophos web Appliance 4.2.1.3
Attack vector
NETWORK Attack complexity
LOW Privileges required
HIGH Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
The Sophos Web Appliance (version 4.2.1.3) is vulnerable to two Remote Command Injection vulnerabilities affecting its web administrative interface. These vulnerabilities occur in the MgrReport.php (/controllers/MgrReport.php) component responsible for blocking and unblocking IP addresses from accessing the device. The device doesn't properly escape the information passed in the variables 'unblockip' and 'blockip' before calling the shell_exec() function which allows for system commands to be injected into the device. The code erroneously suggests that the information handled is protected by utilizing the variable name 'escapedips' - however this was not the case. The Sophos ID is NSWA-1258.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 1 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Cause Web Server Misclassification An attack of this type exploits a Web server's decision to take action based on filename or file extension. Because different file types are handled by different server processes, misclassification may force the Web server to take unexpected action, or expected actions in an unexpected sequence. This may cause the server to exhaust resources, supply debug or system data to the attacker, or bind an attacker to a remote process. This type of vulnerability has been found in many widely used servers including IIS, Lotus Domino, and Orion. The attacker's job in this case is straightforward, standard communication protocols and methods are used and are generally appended with malicious information at the tail end of an otherwise legitimate request. The attack payload varies, but it could be special characters like a period or simply appending a tag that has a special meaning for operations on the server side like .jsp for a java application server. The essence of this attack is that the attacker deceives the server into executing functionality based on the name of the request, i.e. login.jsp, not the contents.
- LDAP Injection An attacker manipulates or crafts an LDAP query for the purpose of undermining the security of the target. Some applications use user input to create LDAP queries that are processed by an LDAP server. For example, a user might provide their username during authentication and the username might be inserted in an LDAP query during the authentication process. An attacker could use this input to inject additional commands into an LDAP query that could disclose sensitive information. For example, entering a * in the aforementioned query might return information about all users on the system. This attack is very similar to an SQL injection attack in that it manipulates a query to gather additional information or coerce a particular return value.
- Command Delimiters An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or a blacklist input validation, as opposed to whitelist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or blacklist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.
- File System Function Injection, Content Based An attack of this type exploits the host's trust in executing remote content including binary files. The files are poisoned with a malicious payload (targeting the file systems accessible by the target software) by the attacker and may be passed through standard channels such as via email, and standard web content like PDF and multimedia files. The attacker exploits known vulnerabilities or handling routines in the target processes. Vulnerabilities of this type have been found in a wide variety of commercial applications from Microsoft Office to Adobe Acrobat and Apple Safari web browser. When the attacker knows the standard handling routines and can identify vulnerabilities and entry points they can be exploited by otherwise seemingly normal content. Once the attack is executed, the attackers' program can access relative directories such as C:\Program Files or other standard system directories to launch further attacks. In a worst case scenario, these programs are combined with other propagation logic and work as a virus.
- Exploiting Multiple Input Interpretation Layers An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.
Exploit-Db
| description | Sophos Web Appliance 4.2.1.3 - block/unblock Remote Command Injection (Metasploit). CVE-2016-9553. Webapps exploit for Hardware platform |
| id | EDB-ID:41413 |
| last seen | 2017-02-21 |
| modified | 2016-12-12 |
| published | 2016-12-12 |
| reporter | Exploit-DB |
| source | https://www.exploit-db.com/download/41413/ |
| title | Sophos Web Appliance 4.2.1.3 - block/unblock Remote Command Injection (Metasploit) |
Nessus
| NASL family | CGI abuses |
| NASL id | SOPHOS_WEB_APPLIANCE_WSA_BUILD_2659463.NASL |
| description | According to its self-reported version number, the Sophos Web Appliance software running on the remote host is prior to 4.3.1. It is, therefore, affected by multiple vulnerabilities : - A remote command injection vulnerability exists in the web administration interface in the /controllers/MgrReport.php script when blocking and unblocking IP addresses due to improper validation of user-supplied input passed to the unblockip |
| last seen | 2020-06-01 |
| modified | 2020-06-02 |
| plugin id | 100846 |
| published | 2017-06-16 |
| reporter | This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof. |
| source | https://www.tenable.com/plugins/nessus/100846 |
| title | Sophos Web Appliance < 4.3.1 Multiple Remote Command Injection Vulnerabilities |
| code | |
Packetstorm
data source https://packetstormsecurity.com/files/download/140807/sophos-exec.txt id PACKETSTORM:140807 last seen 2017-01-31 published 2017-01-31 reporter Russell Sanford source https://packetstormsecurity.com/files/140807/Sophos-Web-Appliance-4.2.1.3-Remote-Command-Injection.html title Sophos Web Appliance 4.2.1.3 Remote Command Injection data source https://packetstormsecurity.com/files/download/141270/sophos_webapp_va_block_unblock_ips_POST_cmdi.rb.txt id PACKETSTORM:141270 last seen 2017-02-24 published 2017-02-24 reporter Russell Sanford source https://packetstormsecurity.com/files/141270/Sophos-Web-Appliance-4.2.1.3-Block-Unblock.html title Sophos Web Appliance 4.2.1.3 Block / Unblock
References
- http://pastebin.com/DUYuN0U5
- http://pastebin.com/DUYuN0U5
- http://swa.sophos.com/rn/swa/concepts/ReleaseNotes_4.3.1.html
- http://swa.sophos.com/rn/swa/concepts/ReleaseNotes_4.3.1.html
- http://www.securityfocus.com/bid/95853
- http://www.securityfocus.com/bid/95853
- https://community.sophos.com/products/web-appliance/b/blog/posts/release-of-swa-version-4-3-1
- https://community.sophos.com/products/web-appliance/b/blog/posts/release-of-swa-version-4-3-1