CVE-2025-12977 (FluentBit Fluent Bit)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.76 % · percentile 55 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- certcc
- NVD status
- Modified
Description
Fluent Bit in_http, in_splunk, and in_elasticsearch input plugins fail to sanitize tag_key inputs. An attacker with network access or the ability to write records into Splunk or Elasticsearch can supply tag_key values containing special characters such as newlines or ../ that are treated as valid tags. Because tags influence routing and some outputs derive filenames or contents from tags, this can allow newline injection, path traversal, forged record injection, or log misrouting, impacting data integrity and log routing.
Weaknesses (CWE)
- CWE-1287 — Improper Validation of Specified Type of Input
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N | CISA-ADP |
| CVSS 3.1 | CRITICAL 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
European references
- ENISA EUVD · EUVD-2025-198811
- GCVE · GCVE-0-2025-12977
CERT-FR advisories
- CERTFR-2025-AVI-1064 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:treasuredata:fluent_bit:4.1.0:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| FluentBit · Fluent Bit | affected 0 < 4.0.12 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |