Horovod contains an insecure deserialization vulnerability in its KVStore HTTP server component
Horovod thru 0.28.1 contains an insecure deserialization vulnerability (CWE-502) in its KVStore HTTP server component. The KVStore server, used for distributed task coordination, lacks authentication and authorization controls, allowing any remote attacker to write arbitrary data via HTTP PUT requests. When a Horovod worker reads data from the KVStore (via HTTP GET), it deserializes the data using cloudpickle.loads() without verifying its source or integrity. An attacker can exploit this by sending a malicious pickle payload to the server before the legitimate data is written, causing the victim worker to deserialize and execute arbitrary code, leading to remote code execution.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | horovod | <= 0.28.1 | no fix |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-502- Platform
- Python (PyPI)
- Package
horovod- Disclosed
- 12.05.2026
- Updated
- 11.10.2026 12:20
Sources and licenses
OSV / GitHub Advisory Database - GHSA-mf8f-x4r3-jm8c - CC BY 4.0
OSV / GitHub Advisory Database - PYSEC-2026-354 - PyPA Advisory Database; CC BY 4.0
Vulnerability history: horovod
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 3
- First → latest
- 03.2022 05.2026
- Without a fix
- 2
- Exploited in attacks
- 0
Severity breakdown
- Critical 2
- High 1
Disclosures per year
- 2022: 1
- 2023: 0
- 2024: 0
- 2025: 1
- 2026: 1
-
Horovod contains an insecure deserialization vulnerability in its KVStore HTTP server component this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.