CVE-2024-21503

Publication date 19 March 2024

Last updated 11 July 2025


Ubuntu priority

Cvss 3 Severity Score

5.3 · Medium

Score breakdown

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.

Status

Package Ubuntu Release Status
black 25.04 plucky
Needs evaluation
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Needs evaluation
23.10 mantic Ignored end of life, was needs-triage
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation

Severity score breakdown

Parameter Value
Base score 5.3 · Medium
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact Low
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L