Answer in brief
CVE-2026-31234 records a Critical severity (CVSS 9.8) vulnerability in Horovod contains an insecure deserialization vulnerability in its KVStore HTTP server component. The current sources do not mark it as known exploited. The current feed maps horovod (pip), horovod (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps horovod (pip), horovod (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| horovodpip | <=0.28.1 | Not reported |
| horovodpypi | >=0 | Not reported |
Published upstream
May 12, 2026
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Oct 27, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Oct 27, 2026
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.
Quoted source text, attributed separately from HOL analysis.