CVE-2025-12969 CVE-2025-12969
Remote attackers can bypass authentication in Fluent Bit's forward input plugin to inject forged logs and manipulate routing when specific configurations are used.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-12969?
CVE-2025-12969 is a medium-severity authentication bypass vulnerability in FluentBit Fluent Bit, published on 24 Nov 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-306
Which versions are affected by CVE-2025-12969?
1 open source package ship an affected version, including fluent-bit. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
fluent-bit Bitnami | From 4.1.0 | 4.1.1 |
Products include Treasuredata Fluent Bit.
How do I fix CVE-2025-12969?
Upgrade fluent-bit to 4.1.1 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-12969 being exploited?
There is no known exploitation of CVE-2025-12969 in the wild and no public exploit code.
Other vulnerabilities in FluentBit Fluent Bit
Sources
Also known as AZL-71077, AZL-71108, BIT-fluent-bit-2025-12969, GHSA-2949-r76x-4vc4.