CVE-2026-25632
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used 10.0
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.
- Record
CVE-2026-25632- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
EUVDEUVD-2026-5576 10.0
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.
- Record
EUVD-2026-5576- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-74vm-8frp-7w68 10.0
EPyT-Flow vulnerable to unsafe JSON deserialization (__type__)
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.
- Record
GHSA-74vm-8frp-7w68- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
NVD 10.0
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.
- Record
CVE-2026-25632- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
OSV 10.0
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.
- Record
CVE-2026-25632- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
OSVGHSA-74vm-8frp-7w68 10.0
EPyT-Flow vulnerable to unsafe JSON deserialization (__type__)
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.
- Record
GHSA-74vm-8frp-7w68- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
OSVPYSEC-2026-330 10.0
EPyT-Flow vulnerable to unsafe JSON deserialization (__type__)
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.
- Record
PYSEC-2026-330- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | lazarus0x1337/CVE-2026-25632 | 2026-07-21 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-25632 is a critical vulnerability (CVSS 10.0) in Waterfutures Epyt-flow, published February 4, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.80%, the 56th percentile. Fixed in epyt-flow 0.16.1.
References
github.com/WaterFutures/EPyT-Flow/security/advisories/GHSA-74vm-8frp-7w68
github.com/WaterFutures/EPyT-Flow/commit/3fff9151494c7dbc72073830b734f0a7e550e385
github.com/WaterFutures/EPyT-Flow/releases/tag/v0.16.1
nvd.nist.gov/vuln/detail/CVE-2026-25632
github.com/pypa/advisory-database/tree/main/vulns/epyt-flow/PYSEC-2026-330.yaml
pypi.org/project/epyt-flow
github.com/advisories/GHSA-74vm-8frp-7w68
github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25632.json
github.com/WaterFutures/EPyT-Flow