CVE-2026-31072
CRITICAL9.8EPSS 0.18%APScheduler's JSONSerializer and CBORSerializer are vulnerable to Remote Code Execution (RCE) via Insecure Deserialization
Published: 5/19/2026Modified: 6/4/2026
Also known as:GHSA-9cfw-f3f9-7mm7
Description
The JSONSerializer and CBORSerializer in APScheduler (all versions including 3.10.x and 4.0.0a5) are vulnerable to Remote Code Execution (RCE) via Insecure Deserialization. The unmarshal_object function allows for arbitrary class instantiation and state injection by dynamically importing modules and calling __setstate__ on any class available in the Python environment. An attacker can exploit this by submitting a specially crafted JSON or CBOR payload to an application using these serializers
Affected packages (2)
- Debian/apschedulerfrom 0
- PyPI/apscheduler>= 4.0.0a1, <= 4.0.0a6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |