CVE-2026-44161highCWE-918

CVE-2026-44161: high-severity vulnerability in fluentd

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

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.2epss 0.4%
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 ${tag} in the endpoint configuration parameter, and if a placeholder value is derived from untrusted input an attacker can control the destination hostname of outbound HTTP requests and force requests to arbitrary internal services. This issue is fixed in version 1.19.3.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:L
Affected products
fluent · fluentd
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CVE-2022-39379LOWFluentd vulnerable to remote code execution due to insecure deserialization (in non-default configuration)EPSS 45.0%CVE-2021-41186MEDIUMReDoS vulnerability in parser_apache2EPSS 2.2%CVE-2026-44024CRITICALFluentd: Remote Code Execution (RCE) via Arbitrary File Write in `${tag}` PlaceholderEPSS 1.1%CVE-2026-44160HIGHFluentd: Denial of Service (DoS) via Gzip Decompression Bomb in `in_http` and `in_forward`EPSS 0.6%CVE-2026-44025HIGHFluentd: Exposure of Sensitive Information via Monitor Agent APIEPSS 0.5%