SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-47103

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 `<data expr="...">` attributes evaluated unsafely.

CRITICAL 9.3EPSS 1.36%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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 `<data expr="...">` 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.

CVSS 4.0
9.3 CRITICALCVSS: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/M
EPSS
1.36% probability · 70th percentile
CISA KEV
Not listed
Weakness
CWE-95, CWE-94
Affected
fgmacedo/python statemachine
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.