CVE-2026-25632

CRITICAL

EPyT-Flow < 0.16.1 - Remote Code Execution via Untrusted JSON Deserialization

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-25632. PoCs published by lazarus0x1337.

AI-analyzed exploit summary This repository provides a detailed technical analysis and proof-of-concept for CVE-2026-25632, an unsafe JSON deserialization vulnerability in the EPyT-Flow Python package leading to Remote Code Execution (RCE). It includes vulnerable and fixed implementations, along with a comprehensive test suite demonstrating the attack vectors and mitigation.

Description

EPyT-Flow is a Python package designed for the easy generation of hydraulic and water quality scenario data of water distribution networks. Prior to 0.16.1, EPyT-Flow’s REST API parses attacker-controlled JSON request bodies using a custom deserializer (my_load_from_json) that supports a type field. When type is present, the deserializer dynamically imports an attacker-specified module/class and instantiates it with attacker-supplied arguments. This allows invoking dangerous classes such as subprocess.Popen, which can lead to OS command execution during JSON parsing. This also affects the loading of JSON files. This vulnerability is fixed in 0.16.1.

Exploits (1)

github WRITEUP 1 stars
by lazarus0x1337 · pythonpoc
https://github.com/lazarus0x1337/CVE-2026-25632

This repository provides a detailed technical analysis and proof-of-concept for CVE-2026-25632, an unsafe JSON deserialization vulnerability in the EPyT-Flow Python package leading to Remote Code Execution (RCE). It includes vulnerable and fixed implementations, along with a comprehensive test suite demonstrating the attack vectors and mitigation.

Classification
Writeup 99%
Attack Type
Deserialization
Complexity
Moderate
Reliability
Reliable
Target: EPyT-Flow Python package (CVE-2026-25632)
No auth needed
Prerequisites: Access to the NovaSim REST API or any service using the vulnerable deserialization pattern · Ability to send crafted JSON payloads with '__type__' field
mistral-large-3 · analyzed Jul 22, 2026 Full analysis →

Scores

CVSS v3 10.0
EPSS 0.0069
EPSS Percentile 49.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-502
Status published
Products (2)
pypi/epyt-flow 0 - 0.16.1PyPI
waterfutures/epyt-flow < 0.16.1
Published Feb 06, 2026
Tracked Since Feb 18, 2026