CVE-2025-12972
mediumpriority · track · 0EPSS 0.009 · 60 %ileDEEURUUSEPSS · scored 2026-10-26
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (7)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2025-2670Fluent Bit: Mehrere SchwachstellenDeutsch2025-11-24csaf · cert_bundDE
Ein entfernter anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Fluent Bit ausnutzen, um Sicherheitsmaßnahmen zu umgehen, beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu verursachen, Daten zu manipulieren und vertrauliche Informationen offenzulegen.
- BIT-fluent-bit-2025-12972CVE-2025-129722025-12-01vendor · osvUS
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.
also known as (4)
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sources
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references (7)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2025-12972cnnvd
- https://fluentbit.io/announcements/v4.1.0/cnnvd
- https://github.com/fluent/fluent-bit/releasesPatchcnnvd
- https://fluentbit.io/blog/2025/10/28/security-vulnerabilities-addressed-in-fluent-bit-v4.1-and-backported-to-v4.0/enisa_euvd
- https://www.oligo.security/blog/critical-vulnerabilities-in-fluent-bit-expose-cloud-environments-to-remote-takeoverenisa_euvd
- https://fluentbit.io/blog/2025/10/28/security-vulnerabilities-addressed-in-fluent-bit-v4.1-and-backported-to-v4.0/nvd
- https://www.oligo.security/blog/critical-vulnerabilities-in-fluent-bit-expose-cloud-environments-to-remote-takeovernvd
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