Vulnerability · CVE-2025-12972
Fluent Bit out_file plugin does not properly sanitize tag values when deriving output file names.
Published Nov 24, 2025 · catalog updated Jan 7, 2026 · FluentBit Fluent Bit
Last checked Oct 30, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2025-12972. EPSS is 0.93%. Act only if a listed version of FluentBit Fluent Bit is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2025-12978 · Medium
- CVE-2025-12969 · Medium
- CVE-2025-12977 · Critical
- CVE-2025-12970 · High
- Severity
- Medium5.3
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.93%
- Remediation
- Version ranges on file
- Affected products
- vendor FluentBit Fluent Bit 0 <4.0.12
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor FluentBit Fluent Bit 0 <4.0.120 <4.0.12
How to fix CVE-2025-12972
Upgrade
CVE-2025-12972 lists a fix boundary at 4.0.12. Compare the installed build with that boundary before you change production.
Version check
Seen in 0 <4.0.12
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-12972. EPSS is 0.93%. Act only if a listed version of FluentBit Fluent Bit is installed.
Which versions are affected?
Compare what you have installed with FluentBit Fluent Bit 0 <4.0.12 0 <4.0.12. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.93%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Nov 24, 2025 · EUVD
Detected
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.
Jan 7, 2026 · EUVD
Updated
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.
Sources
- CVE.orgVulnerability recordCVE-2025-12972
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-12972
30-day exploitation probability 0.93%
first.org - EUVDVulnerability recordEUVD-2025-198810
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 sequen
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 30, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 30, 2026
- CVE.orgOct 27, 2026
- EUVDOct 27, 2026