CVE-2026-32274 HIGH

CVE-2026-32274: Black: Arbitrary file writes from unsanitized user input in cache file name

Vendor Psf
Product black
Weakness CWE-22 · Path traversal
Published March 12, 2026
Last update June 30, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Black is the uncompromising Python code formatter. Prior to 26.3.1, Black writes a cache file, the name of which is computed from various formatting options. The value of the --python-cell-magics option was placed in the filename without sanitization, which allowed an attacker who controls the value of this argument to write cache files to arbitrary file system locations. Fixed in Black 26.3.1.

Key dates

02Disclosure timeline

March 12, 2026 CVE published
June 30, 2026 Record updated