CVE-2026-47103: python-statemachine (PyPI)

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
EPSS 1.4%, percentile 72: FIRST’s model estimates a 1.4% chance of exploitation activity in the next 30 days, higher than 72% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
Only applies if your dependency tree includes python-statemachine (PyPI) >= 3.0.0, < 3.2.0, fixed in 3.2.0. Check your lockfile, including transitive dependencies.

What it is

Python StateMachine versions 3.0.0 before 3.2.0 contains a remote code execution vulnerability that allows attackers to execute arbitrary code by supplying malicious SCXML documents containing crafted attributes evaluated unsafely. The SCXMLProcessor passes attacker-controlled expression strings through a call chain ending in Python's built-in eval() without sandboxing, enabling arbitrary code execution in the context of the hosting process.

From the GitHub advisory

Summary

python-statemachine 3.1.2 evaluates attributes in SCXML documents using Python's eval(). Any application that passes attacker-controlled SCXML content to SCXMLProcessor is vulnerable to arbitrary code execution in the context of the hosting process.

Details

SCXMLProcessor.parsescxmlfile() processes SCXML documents and evaluates element expr attributes via the following call chain:

eval() calls Python's built-in eval() directly on the expression string without sandboxing or restriction.

Weakness type: CWE-95.

Product: python-statemachine (PyPI) · Assigned by: VulnCheck · Published: 2026-06-17

Affected and fixed versions

Ecosystem	Package	Vulnerable	First fixed
PyPI	`python-statemachine`	>= 3.0.0, < 3.2.0	3.2.0

Vendor	Product	Affected versions (per CVE record)
fgmacedo	python-statemachine	3.0.0 < 3.2.0

Severity scores

Scored by	CVSS	Score	Vector
VulnCheck	4.0	9.3 Critical	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`
VulnCheck	3.1	9.8 Critical	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
GitHub	4.0	9.3	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X`

Attack vector: network (remotely reachable)
Attack complexity: low
Attack requirements: none
Privileges required: none (no login)
User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
FIRST EPSS (model of 2026-10-21): 1.37% probability of exploitation activity in the next 30 days; percentile 72.

Timeline

2026-06-17 — CVE record published by VulnCheck
2026-06-18 — GitHub-reviewed advisory GHSA-v4jc-pm6r-3vj8 published (critical)
2026-10-08 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.