CVE-2026-54058 and is rated Critical severity with a CVSS score of 9.1. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CISA KEVNot listedBased on the latest collected catalog
EPSS0.5%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-54058?
Pillow is a Python imaging library. Prior to 12.3.0, when Pillow loads an uncompressed McIdas AREA image from a filename through the mmap raw codec path, attacker-controlled header words can set a row stride smaller than the natural row width, causing pixel access such as Image.tobytes(), getpixel, convert, or save to read beyond the mapped region and disclose adjacent process memory or fault.