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TI-2026-32143 Aliases CVE-2026-44161GHSA-72f5-rr8c-r6gr

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

Priority LOW 38CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00442 38th percentileScored 2026-11-07
Fix Fixed fluentd (fluent): 1.19.3fluentd (RubyGems): 1.19.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
fluentfluentdbefore 1.19.31.19.3Patch availableCNA
—fluentd (RubyGems)before 1.19.31.19.3Patch availableGHSA-72f5-rr8c-r6gr
  • fluentd Vendorfluent Affected before 1.19.3 Fixed in 1.19.3 Patch available CNA
  • fluentd (RubyGems) Vendor— Affected before 1.19.3 Fixed in 1.19.3 Patch available GHSA-72f5-rr8c-r6gr

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fluentd:fluentd:*:*:*:*:*:*:*:*before 1.19.3Vulnerablefluent
  • cpe:2.3:a:fluentd:fluentd:*:*:*:*:*:*:*:* Versions before 1.19.3 Vulnerable ·fluent

Remediation

  • Fix · CNA fluentd (fluent) Fixed in 1.19.3
  • Fix · GHSA-72f5-rr8c-r6gr fluentd (RubyGems) Fixed in 1.19.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-44161
  2. 2026-10-03 Alias added: GHSA-72f5-rr8c-r6gr

References

Patch 2

Advisory 1

Other 2

  • TI-2022-18753 Fluentd vulnerable to remote code execution due to insecure deserialization (in non-default configuration) CVSS 3.1CRITICAL 9.8
  • TI-2026-32064 Fluentd: Remote Code Execution (RCE) via Arbitrary File Write in `${tag}` Placeholder CVSS 3.1CRITICAL 9.8
  • TI-2017-07995 Escape sequence injection vulnerability in Fluentd versions 0.12.29 through 0.12.40 may… CVSS 3.0CRITICAL 9.8
  • TI-2020-14076 An issue was discovered in Fluent-ui v.1.2.2 allows attackers to gain escalated… CVSS 3.1HIGH 8.8
  • TI-2026-32142 Fluentd: Denial of Service (DoS) via Gzip Decompression Bomb in `in_http` and `in_forward` CVSS 3.1HIGH 7.5
  • TI-2026-32065 Fluentd: Exposure of Sensitive Information via Monitor Agent API CVSS 3.1HIGH 7.5
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences