A AegiFlow
CRITICALCVSS 10.0EPSS 0.8%

CVE-2026-25632

EPyT-Flow vulnerable to unsafe JSON deserialization (__type__)

Published
2026-02-04
Modified
2026-10-27
EPSS percentile
57%
Aliases
GHSA-74vm-8frp-7w68
Sources
github-advisory

Summary

### 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.

Affected packages

EcosystemPackageAffected versionsFixed versions
PyPIepyt-flow—0.16.1

Remediation: Upgrade to 0.16.1 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

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EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.