CVE-2026-31072 | The JSONSerializer and CBORSerializer in APScheduler (all ve… | CVSS 9.8 CRITICAL

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

Metadata

CVE ID: CVE-2026-31072
State: PUBLISHED
Assigner: mitre
Reserved: 2026-03-09 00:00 UTC
Published: 2026-05-19 00:00 UTC
Last updated: 2026-07-15 01:09 UTC
Primary CWE: CWE-502
CWE-502 Deserialization of Untrusted Data
Vendor / Product: n/a / n/a
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
n/a	n/a	—	n/a

Weakness (CWE)

CWE	Source	Description
—	cna	n/a
CWE-502	adp	CWE-502 Deserialization of Untrusted Data
CWE-502	adp	Deserialization of Untrusted Data

CVSS scores (2)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	adp	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.8	HIGH	3.1	adp	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References (2)