Vulnerabilities > CVE-2021-29486 - Improper Input Validation vulnerability in Cumulative-Distribution-Function Project Cumulative-Distribution-Function

047910
CVSS 7.5 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
cumulative-distribution-function-project
CWE-20
NVD
Published: 2021-04-30
Updated: 2024-11-21

Summary

cumulative-distribution-function is an open source npm library used which calculates statistical cumulative distribution function from data array of x values. In versions prior to 2.0.0 apps using this library on improper data may crash or go into an infinite-loop. In the case of a nodejs server-app using this library to act on invalid non-numeric data, the nodejs server may crash. This may affect other users of this server and/or require the server to be rebooted for proper operation. In the case of a browser app using this library to act on invalid non-numeric data, that browser may crash or lock up. A flaw enabling an infinite-loop was discovered in the code for evaluating the cumulative-distribution-function of input data. Although the documentation explains that numeric data is required, some users may confuse an array of strings like ["1","2","3","4","5"] for numeric data [1,2,3,4,5] when it is in fact string data. An infinite loop is possible when the cumulative-distribution-function is evaluated for a given point when the input data is string data rather than type `number`. This vulnerability enables an infinite-cpu-loop denial-of-service-attack on any app using npm:cumulative-distribution-function v1.0.3 or earlier if the attacker can supply malformed data to the library. The vulnerability could also manifest if a data source to be analyzed changes data type from Arrays of number (proper) to Arrays of string (invalid, but undetected by earlier version of the library). Users should upgrade to at least v2.0.0, or the latest version. Tests for several types of invalid data have been created, and version 2.0.0 has been tested to reject this invalid data by throwing a `TypeError()` instead of processing it. Developers using this library may wish to adjust their app's code slightly to better tolerate or handle this TypeError. Apps performing proper numeric data validation before sending data to this library should be mostly unaffected by this patch. The vulnerability can be mitigated in older versions by ensuring that only finite numeric data of type `Array[number]` or `number` is passed to `cumulative-distribution-function` and its `f(x)` function, respectively.

Vulnerable Configurations

Part Description Count
Application
Cumulative-Distribution-Function_Project
6

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Server Side Include (SSI) Injection
    An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
  • Cross Zone Scripting
    An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
  • Cross Site Scripting through Log Files
    An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
  • Command Line Execution through SQL Injection
    An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.

References