How severe is CVE-2026-40192?

No CVSS score has been assigned to CVE-2026-40192 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-40192?

CVE-2026-40192 affects the following packages: pillow (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2026-40192?

Update pillow to 12.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40192 is resolved across your whole dependency graph.

How do I detect CVE-2026-40192 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pillow, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-40192 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2026-40192 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-40192 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-40192?

CVE-2026-40192 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 52th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-40192?

CVE-2026-40192 is classified as Uncontrolled Resource Consumption (CWE-400), CWE-770 (CWE-770), CWE-409 (CWE-409). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-40192 published, and has it been updated?

CVE-2026-40192 was published on April 15, 2026 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍 PyPI

Not in CISA KEV

CVE-2026-40192 — pillow

Fix: python-pillow/Pillow@3cb854e

CVE-2026-40192 is a Uncontrolled Resource Consumption vulnerability in pillow. A fix is available for pillow — see the affected versions and patch details below.

Pillow is vulnerable to a FITS GZIP decompression bomb

Also known asBIT-pillow-2026-40192GHSA-whj4-6x5x-4v2jPYSEC-2026-2250

Published

Apr 15, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-40192.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs52th percentile — riskier than 52% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐍pillow

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Pillow did not limit the amount of GZIP-compressed data read when decoding a FITS image, making it 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).

Patches

The amount of data read is now limited to the necessary amount. Fixed in Pillow 12.2.0 (PR #9521).

Workarounds

Avoid Pillow >= 10.3.0, < 12.2.0 Only open specific image formats, excluding FITS.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`pillow`	≥ 10.3.0&&< 12.2.0	12.2.0`pip install --upgrade 'pillow==12.2.0'`

Affected Products

1 product · 1 configurations

Application

pillowpython

≥ 10.3.0 && < 12.2.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pillow, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pillow to 12.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40192 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Source: Red Hat security advisory for CVE-2026-40192 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Ansible Automation Platform 2.5 for RHEL 8	`python3.12-pillow-0:12.2.0-1.el8ap`	RHSA-2026:24761
Red Hat Ansible Automation Platform 2.6 for RHEL 9	`python3.12-pillow-0:12.2.0-1.el9ap`	RHSA-2026:24762
Red Hat Satellite 6.16 for RHEL 8	`python-pillow-0:12.2.0-1.el8pc`	RHSA-2026:27076
Red Hat Satellite 6.17 for RHEL 9	`python-pillow-0:12.2.0-1.el9pc`	RHSA-2026:34366
Red Hat Satellite 6.18 for RHEL 9	`python3.12-pillow-0:12.2.0-1.el9pc`	RHSA-2026:34368
Red Hat Satellite 6.19 for RHEL 9	`python3.12-pillow-0:12.2.0-1.el9pc`	RHSA-2026:34365
Red Hat AI Inference Server 3.2	`rhaiis/vllm-cuda-rhel9:1787860580`	RHSA-2026:61627
Red Hat AI Inference Server 3.2	`rhaiis/model-opt-cuda-rhel9:1787772157`	RHSA-2026:61628

Frequently Asked Questions

### Impact Pillow did not limit the amount of GZIP-compressed data read when decoding a FITS image, making it 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). ### Patches The amount of data read is now limited to the necessary amount. Fixed in Pillow 12.2.0 (PR #9521). ### Workarounds Avoid Pillow >= 10.3.0, < 12.2.0 Only open [specific image formats](https://pillow.readthedocs.io/en/stable/releasenotes/8.0.0.html#image-open-add-formats-parameter), excl

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