CVE-2025-12978

Fluent Bit in_http, in_splunk, and in_elasticsearch input plugins contain a flaw in the tag_key validation logic that fails to enforce exact key-length matching. This allows crafted inputs where a tag prefix is incorrectly treated as a full match. A remote attacker with authenticated or exposed access to these input endpoints can exploit this behavior to manipulate tags and redirect records to unintended destinations. This compromises the authenticity of ingested logs and can allow injection of forged data, alert flooding and routing manipulation.
References
Link Resource
https://fluentbit.io/announcements/v4.1.0/ Release Notes
Configurations

Configuration 1 (hide)

cpe:2.3:a:treasuredata:fluent_bit:4.1.0:*:*:*:*:*:*:*

History

28 Nov 2025, 15:21

Type Values Removed Values Added
CPE cpe:2.3:a:treasuredata:fluent_bit:4.1.0:*:*:*:*:*:*:*
CWE NVD-CWE-noinfo
First Time Treasuredata fluent Bit
Treasuredata
References () https://fluentbit.io/announcements/v4.1.0/ - () https://fluentbit.io/announcements/v4.1.0/ - Release Notes

24 Nov 2025, 16:15

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.4

24 Nov 2025, 15:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-11-24 15:15

Updated : 2025-11-28 15:21


NVD link : CVE-2025-12978

Mitre link : CVE-2025-12978

CVE.ORG link : CVE-2025-12978


JSON object : View

Products Affected

treasuredata

  • fluent_bit