Pillow has an integer overflow when processing fontsGHSA-wjx4-4jcj-g98j
MEDIUMGHSA-wjx4-4jcj-g98j is a medium-severity (CVSS 5.5) CWE-190 vulnerability in pillow. A fix is available for pillow — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- 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 GHSA-wjx4-4jcj-g98j.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
pillowReal-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
Pillow is a Python imaging library. Prior to version 12.2.0, if a font advances for each glyph by an exceeding large amount, when Pillow keeps track of the current position, it may lead to an integer overflow. This issue has been patched in version 12.2.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pillow | all versions | 12.2.0pip install --upgrade 'pillow==12.2.0' |
Affected Products
pillowpythonDetection & mitigation playbook
Open-source dependencyDetect
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 GHSA-wjx4-4jcj-g98j is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.
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.
To mitigate this issue, ensure that applications utilizing the Pillow library do not process untrusted or maliciously crafted font files. Additionally, consider running applications that process image data in a sandboxed environment to limit potential impact. Reloading or restarting affected services may be required for changes to take effect.Source: Red Hat security advisory for GHSA-wjx4-4jcj-g98j (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat AI Inference Server 3.3 | rhaiis/model-opt-cuda-rhel9:1778244559 | RHSA-2026:16008 |
| Red Hat AI Inference Server 3.3 | rhaiis/vllm-rocm-rhel9:1778244531 | RHSA-2026:16009 |
| Red Hat AI Inference Server 3.3 | rhaiis/vllm-cuda-rhel9:1778274666 | RHSA-2026:16030 |
| Red Hat AI Inference Server 3.4 | rhaii/vllm-spyre-rhel9:1787151840 | RHSA-2026:57387 |
Frequently Asked Questions
Is GHSA-wjx4-4jcj-g98j in your dependencies?
Find it across PyPI, including transitive dependencies.