High severity · published Apr 15, 2026
CVE-2026-40192
Pillow is vulnerable to a FITS GZIP decompression bomb
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
Pillow is a Python imaging library. Versions 10.3.0 through 12.1.1 did not limit the amount of GZIP-compressed data read when decoding a FITS image, making them vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation). If users are unable to immediately upgrade, they should only open specific image formats, excluding FITS, as a workaround.
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)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PI
Pillow · python-pillow
>= 10.3.0, < 12.2.0 · source: vendor, NVD
LC
Lightspeed Core · Red Hat
All versions, or not specified · source: CISA
OL
OpenShift Lightspeed · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server 3.2 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server 3.3 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server 3.4 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40192
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40192
Patch
https://github.com/python-pillow/Pillow/commit/3cb854e8b2bab43f40e342e665f9340d861aa628
Issue Tracking
https://github.com/python-pillow/Pillow/pull/9521
Mitigation
https://github.com/python-pillow/Pillow/security/advisories/GHSA-whj4-6x5x-4v2j
Release Notes
https://pillow.readthedocs.io/en/stable/releasenotes/12.2.0.html#prevent-fits-decompression-bomb
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:16008
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:16009
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