Vulnerability in Fluentbit Fluent Bit
CVE-2025-12977
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 ch…
EPSS: 0.006 (45.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Fluentbit Fluent Bit — versions 0
- Treasuredata Fluent_bit — versions 4.1.0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-12977?
- CVE-2025-12977 is a critical-severity vulnerability in Fluentbit Fluent Bit, classified under CWE-1287. CVSS score: 9.1/10. Published 2025-11-24.
- How severe is CVE-2025-12977?
- Critical severity. CVSS v3 base score is 9.1 out of 10.