# CVE-2026-63393: OpenSearch SQL unsafe deserialization in cursor parameter

Source: https://junglewise.ai/threats/cve-2026-63393-opensearch-sql-supports-querying-opensearch-data-using-sql-and  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-30. Updated: 2026-10-30  
License: CC BY 4.0 with a link back

CVE-2026-63393 · Severity: info · Published 2026-10-30

OpenSearch SQL is a query engine that allows users to search data stored in OpenSearch using SQL commands. An authenticated user with basic read permissions can exploit unsafe deserialization in the SQL API to execute arbitrary code on the OpenSearch server, potentially leading to complete system compromise.

Vendors: [OpenSearch Project](https://junglewise.ai/threats/vendors/opensearch-project).

## Quick answers

**Is CVE-2026-63393 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-63393 being exploited in the wild.

**How severe is CVE-2026-63393?** Informational severity, published 30 October 2026.

**Which products and versions are affected?** OpenSearch Project OpenSearch SQL 2.8.0.0 through 2.19.5.0; 3.0.0.0 through 3.6.0.0.

**Is there a fix for CVE-2026-63393?** Yes: fixed in OpenSearch SQL 2.19.6.0, 3.7.0.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-63393 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-63393?** Check whether you run OpenSearch Project OpenSearch SQL at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in OpenSearch SQL 2.19.6.0, 3.7.0.0

## Technical details

The vulnerability exists in the SQL plugin's `/plugins/sql` endpoint, where the `cursor` parameter is deserialized without proper validation, allowing remote code execution. An authenticated attacker with search permissions can craft a malicious cursor parameter to trigger unsafe deserialization of untrusted data. The fix implements ObjectInputFilter to restrict the classes that can be deserialized.

## Affected products

- OpenSearch Project OpenSearch SQL 2.8.0.0 through 2.19.5.0; 3.0.0.0 through 3.6.0.0

## Timeline

- 2026-10-30: disclosed: Vulnerability publicly disclosed
- 2026-10-30: patched: Fix released in versions 2.19.6.0 and 3.7.0.0

## References

- [https://github.com/opensearch-project/sql/commit/402a284f1dff3545236480b67f860aa93fb667de](https://github.com/opensearch-project/sql/commit/402a284f1dff3545236480b67f860aa93fb667de)
- [https://github.com/opensearch-project/sql/commit/9ab50384d3ad571a14211415fba2f6d26d4c80db](https://github.com/opensearch-project/sql/commit/9ab50384d3ad571a14211415fba2f6d26d4c80db)