CVE-2024-21503 (CVSS 5.3)

Description

Versions of the package black before 24.3.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the lines_with_leading_tabs_expanded function in the strings.py file. An attacker could exploit this vulnerability by crafting a malicious input that causes a denial of service. Exploiting this vulnerability is possible when running Black on untrusted input, or if you habitually put thousands of leading tab characters in your docstrings.

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CVSS v3.1 Score

5.3

MEDIUM

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

Weakness Type (CWE)

CWE-1333 CWE-1333

CWE-75 CWE-75

References

Other References

https://github.com/psf/black/commit/f00093672628d212b8965a8993cee8bedf5fe9b8 https://github.com/psf/black/releases/tag/24.3.0 https://security.snyk.io/vuln/SNYK-PYTHON-BLACK-6256273 https://github.com/psf/black/commit/f00093672628d212b8965a8993cee8bedf5fe9b8 https://github.com/psf/black/releases/tag/24.3.0 https://security.snyk.io/vuln/SNYK-PYTHON-BLACK-6256273

Frequently Asked Questions

What is CVE-2024-21503? +

Versions of the package black before 24.3.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the lines_with_leading_tabs_expanded function in the strings.py file. An attacker could exploit this vulnerability by crafting a malicious input that causes a denial of service. Exploiting this vulnerability is possible when running Black on untrusted input, or if you habitually put thousands of leading tab characters in your docstrings. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2024-21503? +

CVE-2024-21503 has a CVSS v3.1 score of 5.3 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-2024-21503? +

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.

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