CVE-2025-6279 — upsonic
Fix: Upsonic/Upsonic#360CVE-2025-6279 is a Improper Input Validation vulnerability in upsonic. A fix is available for upsonic — see the affected versions and patch details below.
Upsonic Pickle add_tool cloudpickle.loads deserialization
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-6279.
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
upsonicReal-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
A vulnerability, which was classified as critical, has been found in Upsonic up to 0.55.6. This issue affects the function cloudpickle.loads of the file /tools/add_tool of the component Pickle Handler. The manipulation leads to deserialization. The exploit has been disclosed to the public and may be used.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | upsonic | all versions | 0.56.0pip install --upgrade 'upsonic==0.56.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for upsonic, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update upsonic to 0.56.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-6279 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-2025-6279 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-6279. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-6279 in your dependencies?
O3 Security finds CVE-2025-6279 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.