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CVE-2026-44024 fluent CVE debrief

Fluentd, a data collector, has a critical vulnerability (CVE-2026-44024) allowing path traversal and potential remote code execution via untrusted tags. The issue is fixed in version 1.19.3. This vulnerability affects Fluentd users, particularly those using versions prior to 1.19.3, who should update to prevent potential remote code execution and data compromise. The vulnerability has a CVSS score of 9.8, indicating critical severity. The attack vector involves dynamically constructing file paths using the ${tag} placeholder, and insufficient validation of ${tag} in file configurations, such as the path parameter of the out_file plugin.

Vendor
fluent
Product
fluentd
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-08
Original CVE updated
2026-07-10
Advisory published
2026-07-08
Advisory updated
2026-07-10

Who should care

Users of Fluentd, especially those using versions prior to 1.19.3, should update to prevent potential remote code execution and data compromise. This includes operators, platform administrators, vulnerability management teams, and security teams who need to assess the vulnerability's impact on their systems and implement necessary mitigations.

Technical summary

CVE-2026-44024 is a critical vulnerability in Fluentd, a data collector, that allows dynamically constructing file paths using the ${tag} placeholder. Insufficient validation of ${tag} in file configurations, such as the path parameter of the out_file plugin, allows attackers sending untrusted tags containing path traversal characters to write or overwrite arbitrary files and potentially achieve remote code execution. The CVSS score is 9.8, indicating critical severity. The issue is fixed in version 1.19.3.

Defensive priority

High priority should be given to updating Fluentd to version 1.19.3 or later to prevent potential exploitation. Additionally, reviewing and validating ${tag} configurations, monitoring logs, and implementing compensating controls are essential to mitigate the vulnerability.

Recommended defensive actions

  • Update Fluentd to version 1.19.3 or later
  • Review and validate ${tag} configurations in file configurations
  • Monitor Fluentd logs for suspicious activity
  • Implement additional security controls to prevent exploitation
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-07-08T22:17:14.337Z and was last modified on 2026-07-10T17:49:57.737Z. The NVD entry is currently Undergoing Analysis. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the vendor. The CVE record and NVD entry provide official details, but additional analysis may be required to fully understand the vulnerability.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-08T22:17:14.337Z and has not been modified since then. The NVD entry is currently Undergoing Analysis.