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Not in CISA KEV
CRITICAL severity

CVE-2020-22083 — jsonpickle

CRITICAL

CVE-2020-22083 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in jsonpickle. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.

jsonpickle unsafe deserialization

Also known asGHSA-j66q-qmrc-89rxPYSEC-2020-49
Published
Updated
Affected
1 pkg
Patched
See advisory
Exploits
1 known
Exploitation data as of Nov 4, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
6.5%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs94th percentile — riskier than 94% of all scored CVEsHighest risk
4.16%5.12%6.08%7.03%4.7%6.5%May 26Sep 26Nov 26

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

1 pkg affected
🐍jsonpickle

Real-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

jsonpickle through 1.4.1 allows remote code execution during deserialization of a malicious payload through the decode() function. Note: It has been argued that this is expected and clearly documented behaviour. pickle is known to be capable of causing arbitrary code execution, and must not be used with un-trusted data

Affected Packages

1 total
EcosystemPackageVulnerable rangeFix
🐍PyPIjsonpickleall versionsNo fix

Affected Products

1 product · 1 configurations
Application
jsonpicklejsonpickle_project
≤ 1.4.1
range
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jsonpickle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Remediation status

    The records we use list no patched version of jsonpickle for CVE-2020-22083. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.

  3. Mitigate without a patch

    Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

Frequently Asked Questions

jsonpickle through 1.4.1 allows remote code execution during deserialization of a malicious payload through the decode() function. Note: It has been argued that this is expected and clearly documented behaviour. pickle is known to be capable of causing arbitrary code execution, and must not be used with un-trusted data
O3 Security · Impact-Aware SCA

Is CVE-2020-22083 in your dependencies?

Find it across PyPI, including transitive dependencies.

CVE-2020-22083: jsonpickle RCE (Critical 9.8)