CVE-2024-34075

MEDIUM
Published May 3, 2024 Modified Apr 15, 2026 CWE-502

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.

Is your site exposed to CVE-2024-34075?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

6.2
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-502 Deserialization of Untrusted Data

References

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. It has a CVSS v3.1 base score of 6.2 (MEDIUM).
How severe is CVE-2024-34075? +
CVE-2024-34075 has a CVSS v3.1 score of 6.2 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2024-34075? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2024-34075 — free, no signup required.