RCE via Prototype Pollution in OpenSearch Dashboards
Priority MEDIUM 42CWE-1321Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
Improper input validation in the Time Series Visual Builder (TSVB) plugin in OpenSearch Dashboards allows an authenticated remote user to execute arbitrary code on the server via a crafted JSON payload to the metrics visualization API endpoint. This issue is a form of prototype pollution that enables remote code execution. To remediate this issue, users should upgrade to OpenSearch Dashboards 3.8 or later.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00962 61st percentileScored 2026-11-07
Fix Fixed Amazon OpenSearch Service (AWS): 3.8.0OpenSearch Dashboards (OpenSearch): 3.8.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| AWS | Amazon OpenSearch Service | 3.0.0 to before 3.8.0 | 3.8.0 | Patch available | CNA |
| OpenSearch | OpenSearch Dashboards | 3.0.0 to before 3.8.0 | 3.8.0 | Patch available | CNA |
- Amazon OpenSearch Service VendorAWS Affected 3.0.0 to before 3.8.0 Fixed in 3.8.0 Patch available CNA
- OpenSearch Dashboards VendorOpenSearch Affected 3.0.0 to before 3.8.0 Fixed in 3.8.0 Patch available CNA
Remediation
- Fix · CNA Amazon OpenSearch Service (AWS) Fixed in 3.8.0
- Fix · CNA OpenSearch Dashboards (OpenSearch) Fixed in 3.8.0
Timeline
- 2026-10-02 Threatist record created from CVE-2026-18420
- 2026-10-03 Alias added: GHSA-jhcc-gw3q-f4pc
- 2026-10-06 EPSS moved to the 50th–90th percentile
References
More AWS vulnerabilities
- TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2024-18648 Amazon AWS Amplify CLI before 12.10.1 incorrectly configures the role trust policy of IAM… CVSS 3.1CRITICAL 9.8
- TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
- TI-2025-03847 Input validation issue in AWS Amplify Studio UI component properties CVSS 4.0CRITICAL 9.0
- TI-2026-11603 HTTP/2 Stream Parser Confusion Body-Inspection Bypass in Amazon CloudFront with AWS WAF CVSS 4.0HIGH 7.9
Sources
- CVE-2026-18420 · CVE Program
- CVE-2026-18420 · NVD
- FIRST EPSS
- GHSA-jhcc-gw3q-f4pc · GitHub Advisory Database · CC BY 4.0
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