GHSA-8843-m7mw-mxqm is a high-severity (CVSS 7.8) CWE-120 vulnerability in pillow. O3 Security confirms whether GHSA-8843-m7mw-mxqm is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Buffer overflow in Pillow
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
In Pillow before 7.1.0, there are two Buffer Overflows in libImaging/TiffDecode.c.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pillow | all versions | 7.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pillow. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pillow to 7.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8843-m7mw-mxqm is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-8843-m7mw-mxqm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-8843-m7mw-mxqm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
While python-pillow is listed as a dependency of Red Hat Quay, it is not used by the application. This issue did not affect the versions of python-pillow as shipped with Red Hat Enterprise Linux 5, 6, 7, and 8 as they provide an older version of the code which does not include the vulnerable code.
Frequently Asked Questions
Is GHSA-8843-m7mw-mxqm in your dependencies?
O3 detects GHSA-8843-m7mw-mxqm across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.