High severity · published Jul 6, 2026
CVE-2026-54059
Pillow: PcfFontFile._load_bitmaps()`: `Image.frombytes()` called without `_decompression_bomb_check()` — bomb protection bypass via PCF font loading
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Pillow is a Python imaging library. Prior to 12.3.0, PIL/PcfFontFile.py _load_bitmaps() read glyph dimensions from the PCF METRICS section and passed them directly to Image.frombytes() without calling Image._decompression_bomb_check(), allowing crafted PCF font data to cause excessive memory allocation. This issue is fixed in version 12.3.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PI
Pillow · python-pillow
< 12.3.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54059
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-54059
Release Notes
https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst
Patch
https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d
Exploit
https://github.com/python-pillow/Pillow/security/advisories/GHSA-8v84-f9pq-wr9x
More from Pillow
9.8
CVE-2026-96639
Pillow multi-frame loaders can reuse stale native image storage after mode transitions
9.8
CVE-2026-112900
Pillow: Argument Injection in Ghostscript call, potentially leading into RCE
9.8
CVE-2026-112403
Pillow: Heap buffer overflow in ImagingJpegDecode
9.8
CVE-2026-112398
Pillow: Heap buffer overflow in FlashPix (FPX) JPEG decoding leads to code execution
9.8
CVE-2026-112393
Pillow: Heap buffer overflow in _tiffWriteProc when saving TIFF to BytesIO