CVE-2026-31072

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

Published: 2026-05-19 Last update: 2026-05-20 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-31072 is rated Moderate Risk (52.8/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.18%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-31072

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-25 0.13% 0.18% +0.04%
2 2026-05-22 0.39% 0.13% -0.26%
3 2026-05-21 — 0.39% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-31072

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-31072

GitHub Security Advisory for CVE-2026-31072

GHSA-9cfw-f3f9-7mm7 · Severity: critical · Ecosystem: pip — APScheduler's JSONSerializer and CBORSerializer are vulnerable to Remote Code Execution (RCE) via Insecure Deserialization

OS Trackers for CVE-2026-31072

vendor priority summary link
debian not yet assigned CVE-2026-31072 not yet assigned priority: Debian including 1 source packages (apscheduler), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. https://security-tracker.debian.org/tracker/CVE-2026-31072
redhat high — https://access.redhat.com/security/cve/CVE-2026-31072
suse high CVE-2026-31072 severity important: SUSE including 1 source package names (python-APScheduler), 1 product×package rows across 1 product lines (SUSE Linux Enterprise Module for Public Cloud 12): Known Not Affected 1. https://www.suse.com/security/cve/CVE-2026-31072/
ubuntu medium CVE-2026-31072 medium priority: Ubuntu including 1 source packages (apscheduler), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): not-affected 6, released 1. https://ubuntu.com/security/CVE-2026-31072

Affected software / configurations for CVE-2026-31072

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-31072

cvelogic Threat Intelligence