CVE-2025-12977

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2025-12977
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-12977.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2025-12977
Aliases
Downstream
Published
2025-11-24T14:40:12.642Z
Modified
2026-07-15T01:49:21.210841948Z
Severity
  • 9.1 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
CVE-2025-12977
Details

Fluent Bit inhttp, insplunk, and inelasticsearch input plugins fail to sanitize tagkey 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.

Database specific 
{
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "fixed": "4.0.12"
                }
            ]
        }
    ],
    "cna_assigner": "certcc",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/12xxx/CVE-2025-12977.json"
}
References

Affected packages

Git / github.com/fluent/fluent-bit

Affected ranges

Type
GIT
Repo
https://github.com/fluent/fluent-bit
Events
Introduced
a8bd9e4cf636710dc7ce3af9d940bb4d91e660fc
Last affected
a8bd9e4cf636710dc7ce3af9d940bb4d91e660fc
Database specific 
{
    "cpe": "cpe:2.3:a:treasuredata:fluent_bit:4.1.0:*:*:*:*:*:*:*",
    "source": "CPE_STRING",
    "extracted_events": [
        {
            "introduced": "4.1.0"
        },
        {
            "last_affected": "4.1.0"
        }
    ]
}

Affected versions

4.*
4.1.0
v4.*
v4.1.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-12977.json"