CVE-2026-44161

HIGH7.2

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

Published Jul 8, 2026

Modified 2 months ago

Details

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.

References

WEB

https://github.com/fluent/fluentd/commit/c6a01ea2e0ea01977f8d615f7c6dbfae4cba88c9

WEB

https://github.com/fluent/fluentd/pull/5394

WEB

https://github.com/fluent/fluentd/releases/tag/v1.19.3

WEB

https://github.com/fluent/fluentd/security/advisories/GHSA-72f5-rr8c-r6gr

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-44161

CVSS Analysis