CVE-2026-32640 — simpleeval
CVE-2026-32640 is a Code Injection vulnerability in simpleeval. A fix is available for simpleeval — see the affected versions and patch details below.
(SimpleEval) Objects (including modules) can leak dangerous modules through to direct access inside the sandbox.
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-2026-32640.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
simpleevalReal-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
If the objects passed in as names to SimpleEval have modules or other disallowed / dangerous objects available as attrs.
Additionally, dangerous functions or modules could be accessed by passing them as callbacks to other safe functions to call.
Examples (found by @ByamB4):
Any module where non-underscore attribute chains reach os or sys:
- os.path, pathlib, shutil, glob (direct .os / .sys attributes)
- statistics (has .sys)
- numpy (has .ctypeslib.os and .f2py.sys)
- urllib.parse (has .warnings.sys)
Patches
The latest version 1.0.5 has this issue fixed.
Workarounds
Don't pass in objects or modules which have direct attributes to potentially dangerous items. Use a wrapper to wrap the potentially vulnerable items (See the ModuleWrapper in version 1.0.5)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | simpleeval | all versions | 1.0.5pip install --upgrade 'simpleeval==1.0.5' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simpleeval, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update simpleeval to 1.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-32640 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-32640 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-32640. 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.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift AI 2.25 | rhoai/odh-training-cuda121-torch24-py311-rhel9:1776243258 | RHSA-2026:10184 |
| Red Hat OpenShift AI 3.3 | rhoai/odh-trustyai-nemo-guardrails-server-rhel9:1782471606 | RHSA-2026:37275 |
Frequently Asked Questions
Is CVE-2026-32640 in your dependencies?
O3 Security finds CVE-2026-32640 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.