CVE-2025-12970
Published: 24 November 2025
Description
The extract_name function in Fluent Bit in_docker input plugin copies container names into a fixed size stack buffer without validating length. An attacker who can create containers or control container names, can supply a long name that overflows the buffer,…
more
leading to process crash or arbitrary code execution.
Mitigating Controls (NIST 800-53 r5)AI
Requires timely remediation of flaws, such as patching Fluent Bit to version 4.1 or later, directly eliminating the buffer overflow vulnerability in the in_docker plugin.
Mandates validation of information inputs like container names to ensure length checks prevent stack buffer overflows during copying operations.
Provides memory protections such as stack canaries or address space layout randomization that mitigate exploitation of stack-based buffer overflows even if input validation fails.
Security SummaryAI
CVE-2025-12970 is a buffer overflow vulnerability (CWE-120) in the extract_name function of the in_docker input plugin in Fluent Bit. The function copies container names into a fixed-size stack buffer without validating the input length, which can lead to a stack-based buffer overflow. This issue affects Fluent Bit deployments that utilize the in_docker plugin for monitoring Docker containers, with a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
An attacker with low privileges (PR:L) who can create containers or control container names can exploit this vulnerability over the network with low complexity and no user interaction required. By supplying an excessively long container name, the attacker triggers the buffer overflow, potentially causing a denial-of-service via process crash or achieving arbitrary code execution with high impact on confidentiality, integrity, and availability.
Advisories from Fluent Bit and security researchers indicate that the vulnerability has been addressed in Fluent Bit version 4.1, with backports available for version 4.0. Security practitioners should update to these patched versions and review configurations using the in_docker plugin in cloud or containerized environments.
Details
- CWE(s)
Affected Products
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Buffer overflow in Fluent Bit's in_docker plugin enables RCE or DoS when triggered by controlled container names, facilitating container escape to host (T1611) and exploitation for privilege escalation (T1068) from low-privileged container access.