CVE-2024-34075: kurwov is a fast, dependency-free library for creating Markov Chains. An unsafe sanitization of dataset contents on the `MarkovData#getNext` method us...

Description

kurwov is a fast, dependency-free library for creating Markov Chains. An unsafe sanitization of dataset contents on the `MarkovData#getNext` method used in `Markov#generate` and `Markov#choose` allows a maliciously crafted string on the dataset to throw and stop the function from running properly. If a string contains a forbidden substring (i.e. `__proto__`) followed by a space character, the code will access a special property in `MarkovData#finalData` by removing the last character of the string, bypassing the dataset sanitization (as it is supposed to be already sanitized before this function is called). Any dataset can be contaminated with the substring making it unable to properly generate anything in some cases. This issue has been addressed in version 3.2.5 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

Metrics

CVSS 3.1

6.2/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.30%

21.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-502

References

Timeline

Published: May 3, 2024
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2024-34075?

kurwov is a fast, dependency-free library for creating Markov Chains. An unsafe sanitization of dataset contents on the `MarkovData#getNext` method used in `Markov#generate` and `Markov#choose` allows a maliciously crafted string on the dataset to throw and stop the function from running properly. If a string contains a forbidden substring (i.e. `__proto__`) followed by a space character, the code will access a special property in `MarkovData#finalData` by removing the last character of the string, bypassing the dataset sanitization (as it is supposed to be already sanitized before this function is called). Any dataset can be contaminated with the substring making it unable to properly generate anything in some cases. This issue has been addressed in version 3.2.5 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

How severe is CVE-2024-34075?

CVE-2024-34075 has a CVSS score of 6.2/10 (MEDIUM severity). The EPSS model estimates a 0.30% probability of exploitation in the next 30 days.

How do I fix CVE-2024-34075?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.