Vulnerabilities > CVE-2016-3954 - Information Exposure vulnerability in Web2Py
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
NONE Summary
web2py before 2.14.2 allows remote attackers to obtain the session_cookie_key value via a direct request to examples/simple_examples/status. NOTE: this issue can be leveraged by remote attackers to execute arbitrary code using CVE-2016-3957.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Subverting Environment Variable Values The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
- Footprinting An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
- Exploiting Trust in Client (aka Make the Client Invisible) An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
- Browser Fingerprinting An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
- Session Credential Falsification through Prediction This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.
Nessus
| NASL family | Ubuntu Local Security Checks |
| NASL id | UBUNTU_USN-4030-1.NASL |
| description | It was discovered that web2py does not properly check denied hosts before verifying passwords. An attacker could possibly use this issue to perform brute-force attacks. (CVE-2016-10321) It was discovered that web2py allows remote attackers to obtain environment variable values. An attacker could possibly use this issue to gain administrative access. (CVE-2016-3952) It was discovered that web2py uses a hardcoded encryption key. An attacker could possibly use this issue to execute arbitrary code. (CVE-2016-3953, CVE-2016-3954, CVE-2016-3957). Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. |
| last seen | 2020-06-01 |
| modified | 2020-06-02 |
| plugin id | 126174 |
| published | 2019-06-24 |
| reporter | Ubuntu Security Notice (C) 2019-2020 Canonical, Inc. / NASL script (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof. |
| source | https://www.tenable.com/plugins/nessus/126174 |
| title | Ubuntu 16.04 LTS : web2py vulnerabilities (USN-4030-1) |
| code | |