CVE-2026-44161

Fluentd: Server-Side Request Forgery (SSRF) via Placeholder Expansion in `out_http`

Published Jul 8, 2026 CVSS 3.1 · 7.2 High EPSS < 1% KEV · Not listed
Description
Fluentd collects events from various data sources and writes them to files, RDBMS, NoSQL, IaaS, SaaS, Hadoop and so on. Prior to 1.19.3, the Fluentd out_http output plugin allows placeholders such as ${tag} in the endpoint configuration parameter, and if a placeholder value is derived from untrusted input an attacker can control the destination hostname of outbound HTTP requests and force requests to arbitrary internal services. This issue is fixed in version 1.19.3.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-72f5-rr8c-r6gr Fluentd is Vulnerable to Server-Side Request Forgery (SSRF) via Placeholder Expansion in `out_http`
History
Type Values Removed Values Added
First Time appeared Fluentd
Fluentd fluentd
Vendors & Products Fluentd
Fluentd fluentd
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Fluentd collects events from various data sources and writes them to files, RDBMS, NoSQL, IaaS, SaaS, Hadoop and so on. Prior to 1.19.3, the Fluentd out_http output plugin allows placeholders such as ${tag} in the endpoint configuration parameter, and if a placeholder value is derived from untrusted input an attacker can control the destination hostname of outbound HTTP requests and force requests to arbitrary internal services. This issue is fixed in version 1.19.3.
Title Fluentd: Server-Side Request Forgery (SSRF) via Placeholder Expansion in `out_http`
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 7.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 9, 2026, 2:40 PM
Reserved
May 5, 2026, 2:39 PM
Status
Analyzed
Published
Jul 8, 2026, 10:17 PM
Modified
Oct 25, 2026, 5:10 PM