CVE-2020-20136 json
QuantConnect Lean vulnerable to insecure deserialization
published 2020-12-14 5 y ago modified 2026-06-17 4 mo ago also GHSA-ww7r-278h-48mh , EUVD-2022-5652
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 75%
- public exploits
- 0
- none known
Summary
QuantConnect Lean versions from 2.3.0.0 to 2.4.0.1 are affected by an insecure deserialization vulnerability due to insecure configuration of TypeNameHandling property in Json.NET library.
Exploit prediction
1.54% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/QuantConnect/Lean/issues/3537 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| nuget | QuantConnect.Common | >=2.3.0.0, <=2.4.0.1 |
no fix listed |
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
References
-
github.com
/QuantConnect/Lean/issues/3537
web, exploit, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2020-20136
advisory
-
github.com
/QuantConnect/Lean
package
Sources
- CVE List CVE-2020-20136
- GitHub Advisory GHSA-ww7r-278h-48mh
- NVD CVE-2020-20136
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