High severity · published Aug 13, 2026
CVE-2026-18428
SQL Query Validation Bypass in OpenSearch Direct Query
8.8
CVSS
1%
EPSS
No
On KEV
Description
A SQL query validation bypass in the Flint extension query handler in the OpenSearch SQL plugin allows a remote authenticated actor with async query access to execute arbitrary code on Apache Spark workers by sending a crafted SQL query to the direct query endpoint.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
Opensearch · AWS
2.13 through 3.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18428
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18428
aws.amazon.com
https://aws.amazon.com/security/security-bulletins/2026-081-aws/
docs.aws.amazon.com
https://docs.aws.amazon.com/opensearch-service/latest/developerguide/service-software.html
github.com
https://github.com/opensearch-project/sql/security/advisories/GHSA-g4jr-343c-fvjm
opensearch.org
https://opensearch.org/artifacts/by-version/?_gl=1*d14pqp*_up*MQ..*_ga*Nzc5NTAxNzM2LjE3ODM1NTA2NDA.*_ga_BQV14XK08F*czE3ODM1NTA2NDAkbzEkZzEkdDE3ODM1NTA3MTQkajU2JGwwJGg3NTc4ODY0OTM.#release-2-19-6
opensearch.org
https://opensearch.org/artifacts/by-version/?_gl=1*d14pqp*_up*MQ..*_ga*Nzc5NTAxNzM2LjE3ODM1NTA2NDA.*_ga_BQV14XK08F*czE3ODM1NTA2NDAkbzEkZzEkdDE3ODM1NTA3MTQkajU2JGwwJGg3NTc4ODY0OTM.#release-3-7-0
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