CVE-2021-29486

cumulative-distribution-function Infinite Loop vulnerability

Workarounds

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.

For more information

If you have any questions or comments about this advisory:

• Open an issue in the Github repository at https://github.com/DrPaulBrewer/cumulative-distribution-function

• 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).

The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.

CVE-2021-29486 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.0.0); upgrading removes the vulnerable code path.

Kodem intelligence

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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.

1. What is CVE-2021-29486? CVE-2021-29486 is a high-severity improper input validation vulnerability in cumulative-distribution-function (npm), affecting versions < 2.0.0. It is fixed in 2.0.0. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
2. How severe is CVE-2021-29486? CVE-2021-29486 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of cumulative-distribution-function are affected by CVE-2021-29486? cumulative-distribution-function (npm) versions < 2.0.0 is affected.
4. Is there a fix for CVE-2021-29486? Yes. CVE-2021-29486 is fixed in 2.0.0. Upgrade to this version or later.
5. Is CVE-2021-29486 exploitable, and should I be worried? Whether CVE-2021-29486 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2021-29486 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2021-29486? Upgrade cumulative-distribution-function to 2.0.0 or later.