CVE-2025-12977 (GCVE-0-2025-12977)

Vulnerability from cvelistv5 – Published: 2025-11-24 14:40 – Updated: 2026-01-07 15:36
VLAI
Title
CVE-2025-12977
Summary
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.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-11-24 19:12 UTC
CWE
  • CWE-187 - Partial String Comparison
  • CWE-1287 - Improper Validation of Specified Type of Input
Assigner
certcc CNA under the mitre root
CNA scorecard E 42/100 over 158 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
FluentBit Fluent Bit Affected: 0 , < 4.0.12 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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