CVE-2026-78605

Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') (CWE-444) in Elasticsearch can lead to information disclosure via HTTP Request Smuggling (CAPEC-33). Under specific proxy deployment configurations, a network attacker could obtain confidential responses intended for other authenticated users.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-141/390092	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:elastic:elasticsearch::::::::
	cpe:2.3:a:elastic:elasticsearch::::::::
	cpe:2.3:a:elastic:elasticsearch:9.5.0:::::::*

History

No history.

Information

Published : 2026-09-01 20:17

Updated : 2026-09-02 18:50

NVD link : CVE-2026-78605

Mitre link : CVE-2026-78605

CVE.ORG link : CVE-2026-78605

JSON object : View

Products Affected

elastic

elasticsearch

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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