Vulnerability · Published Nov 24, 2025 · Assigned by certcc
CVE-2025-12972CVE-2025-12972
Medium 5.3
In plain English
A medium-severity security flaw in Fluent Bit from FluentBit. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 61% of all known vulnerabilities).
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.9%top 39.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Fluent Bit out_file plugin does not properly sanitize tag values when deriving output file names. When the File option is omitted, the plugin uses untrusted tag input to construct file paths. This allows attackers with network access to craft tags containing path traversal sequences that cause Fluent Bit to write files outside the intended output directory.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| FluentBit | Fluent Bit | 0 – before 4.0.12 |