CVE-2025-12978

CVE-2025-12978

Published Nov 24, 2025 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
First Time appeared Treasuredata
Treasuredata fluent Bit
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:a:treasuredata:fluent_bit:4.1.0:*:*:*:*:*:*:*
Vendors & Products Treasuredata
Treasuredata fluent Bit
Type Values Removed Values Added
First Time appeared Fluentbit
Fluentbit fluent Bit
Vendors & Products Fluentbit
Fluentbit fluent Bit
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title CVE-2025-12978
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
certcc
Published
Updated
Jan 7, 2026, 3:36 PM
Reserved
Nov 10, 2025, 6:57 PM
Status
Analyzed
Published
Nov 24, 2025, 3:15 PM
Modified
Oct 8, 2026, 10:10 AM