# CVE-2025-12972: Fluent Bit out_file plugin does not properly sanitize tag values when deriving output file names. When the File option…

Source: https://junglewise.ai/threats/cve-2025-12972-fluent-bit-out-file-plugin-does-not-properly-sanitize-tag-values  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-11-24  
License: CC BY 4.0 with a link back

CVE-2025-12972 · Severity: medium · CVSS 5.3 · Published 2025-11-24

Fluent Bit out_file plugin does not properly sanitize tag values when deriving output file names. When the File option is omitted, the plugin uses untrusted tag input to construct file paths. This allows attackers with network access to craft tags containing path traversal sequences that cause Fluent Bit to write files outside the intended output directory.

Technologies: [Treasuredata Fluent Bit](https://junglewise.ai/threats/technologies/treasuredata-fluent-bit). Vendors: [Treasuredata](https://junglewise.ai/threats/vendors/treasuredata).

## Quick answers

**Is CVE-2025-12972 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-12972 being exploited in the wild.

**How severe is CVE-2025-12972?** Medium severity, with a CVSS score of 5.3, published 24 November 2025.

**Which products and versions are affected?** Treasuredata Fluent Bit. The advisory does not name versions.

**Is there a fix for CVE-2025-12972?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2025-12972?** Check whether you run Treasuredata Fluent Bit. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Treasuredata Fluent Bit

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