CVE-2025-12969

24.11.2025, 15:15

Fluent Bit in_forward input plugin does not properly enforce the security.users authentication mechanism under certain configuration conditions. This allows remote attackers with network access to the Fluent Bit instance exposing the forward input to send unauthenticated data. By bypassing authentication controls, attackers can inject forged log records, flood alerting systems, or manipulate routing decisions, compromising the authenticity and integrity of ingested logs.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	NIST	6.5 MEDIUM	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
certcc	CNA	---				---
CISA-ADP	ADP	6.5 MEDIUM	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Awaiting analysis

This vulnerability is currently awaiting analysis.

Base Score

CVSS 3.x

EPSS Score

Percentile: 15%

Vulnerability Media Exposure

[ENGLISH] New Fluent Bit Flaws Expose Cloud to RCE and Stealthy Infrastructure Intrusions
Cybersecurity researchers have discovered five vulnerabilities in Fluent Bit, an open-source and lightweight telemetry agent, that could be chained to compromise and take over cloud infrastructures. The security defects "allow attackers to bypass authentication, perform path traversal, achieve remote code execution, cause denial-of-service conditions, and manipulate tags," Oligo Security said in
Published: 2025-11-24T20:33:00+05:30
[ENGLISH] Years-old bugs in open source tool left every major cloud open to disruption
Fluent Bit has 15B+ deployments … and 5 newly assigned CVEs A series of "trivial-to-exploit" vulnerabilities in Fluent Bit, an open source log collection tool that runs in every major cloud and AI lab, was left open for years, giving attackers an exploit chain to completely disrupt cloud services and alter data.…
Published: 2025-11-24T15:23:47+00:00
[GERMAN] Fluent Bit: Große Clouddienste durch Bugs in Open-Source-Tool gefährdet
Konzerne wie AWS, Microsoft und Google setzen Fluent Bit ein. Angreifer hätten deren Cloudsysteme durch Sicherheitslücken kapern können. ( Sicherheitslücke , AWS )
Published: 2025-11-25T10:46:08+01:00
[GERMAN] Fluent Bit: Mehrere Schwachstellen
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.
Published: 2025-11-24T23:00:00+00:00

References

https://fluentbit.io/announcements/v4.1.0/