2026-02-06 20:24CVE-2026-25632GitHub_M
PUBLISHED5.2CWE-502

EPyT-Flow has unsafe JSON deserialization (__type__)

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.

Problem type

Affected products

WaterFutures

EPyT-Flow

< 0.16.1 - AFFECTED

References

GitHub Security Advisories

GHSA-74vm-8frp-7w68

EPyT-Flow vulnerable to unsafe JSON deserialization (__type__)

https://github.com/advisories/GHSA-74vm-8frp-7w68

Impact

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.

Patches

EPyT-Flow has been patched in 0.16.1 -- affects all versions <= 0.16.0

Workarounds

Do not load any JSON from untrusted sources and do not expose the REST API.

Credits

EPyT-Flow thanks Jarrett Chan (@syphonetic) for detecting and reporting the bug.

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-25632
Click to expand
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