CVE-2025-12970: High Vulnerability in TreasureData Fluent Bit

CVE-2025-12970 is a high-severity vulnerability affecting the fluent_bit component of TreasureData. This vulnerability allows attackers to exploit a buffer overflow due to the extract_name function in the in_docker input plugin. The function copies container names into a fixed-size stack buffer without validating their length, making it susceptible to overflow. The CVSS score for this vulnerability is 8.8, highlighting its critical nature.

Organizations that utilize fluent_bit must understand the potential risks associated with this vulnerability. An attacker capable of creating containers or controlling their names could supply an excessively long name, leading to a process crash or even arbitrary code execution. Risk to organizations includes unauthorized access and system compromise, prompting the need for immediate action.

Currently, no public exploits have been confirmed, but the exploitability of this vulnerability is considered high. Organizations should prioritize patching immediately to mitigate the risk of exploitation and protect their systems from potential threats.

In summary, CVE-2025-12970 presents a significant risk to organizations using fluent_bit. The combination of its high CVSS score and the potential for severe impacts necessitates urgent remediation efforts.

Vulnerability Details

The extract_name function in Fluent Bit's in_docker input plugin is vulnerable due to its inability to validate the length of container names before copying them into a fixed-size stack buffer. As a result, this oversight allows attackers to create containers with excessively long names, leading to a buffer overflow condition. The vulnerability falls under the CWE-120 classification.

The CVSS score of 8.8 categorizes this vulnerability as high severity. The details of the CVSS vector indicate that the attack vector is network-based (AV:N), requires low complexity (AC:L), and low privileges (PR:L) with no user interaction (UI:N). The impacts on confidentiality, integrity, and availability are all rated as high (C:H, I:H, A:H).

The vulnerability was published on November 24, 2025, and affects fluent_bit versions prior to the vendor's patch. The last known modification to the CVE record occurred shortly after its publication.

Technical Analysis

The root cause of CVE-2025-12970 lies in the insufficient validation of input length within the extract_name function. This design flaw allows for an attacker to exploit the function by supplying a container name that exceeds the buffer size, thus leading to a buffer overflow. The attack vector is network-based (AV:N), as it relies on an attacker’s ability to communicate with the affected system over a network.

The attack complexity is rated as low (AC:L), which means that the attacker does not need any specialized conditions to exploit the vulnerability. Privileges required are also low (PR:L), meaning an attacker can exploit this vulnerability without needing elevated privileges. Importantly, user interaction is not required (UI:N) to successfully exploit the vulnerability.

The impact on confidentiality, integrity, and availability is high (C:H, I:H, A:H), signaling that successful exploitation can lead to sensitive data exposure, unauthorized changes, or service interruptions.

Risk & Impact Analysis

The risk to organizations includes potential unauthorized access and a complete compromise of affected systems. Attackers may leverage this vulnerability to execute arbitrary code, resulting in severe ramifications for data integrity and system availability. Organizations utilizing fluent_bit in their environments, especially those managing sensitive data, should consider the potential blast radius of an attack leveraging this vulnerability.

Given the high CVSS score and the fact that no public exploit has been confirmed does not mitigate the urgency of this vulnerability. Organizations should address this issue in their priority patch cycle to ensure the continued security of their systems.

Organizations should assess their exposure to this vulnerability and take proactive measures to mitigate risks, including updating their systems to the latest patched version of fluent_bit.

Exploitation Status

Affected Versions

The affected version is fluent_bit version 4.1.0. Organizations should upgrade to the latest patched version to mitigate the risk associated with this vulnerability.

Mitigation & Remediation

Organizations must prioritize patching to the latest version of fluent_bit to eliminate this vulnerability. If immediate patching is not possible, consider implementing configuration hardening measures to limit access to container creation and naming.

For additional guidance on security testing and vulnerability management, organizations can refer to the penetration testing services offered by AppSecure.

Detection Guidance

To detect attempts to exploit this vulnerability, organizations should monitor logs for any anomalies related to container creation and naming conventions. Behavioral indicators of compromise may include unexpected crashes of fluent_bit or unusual container names appearing in logs.

AppSecure Threat Intelligence Insight

This vulnerability represents a critical risk for organizations leveraging fluent_bit, especially those in environments where container management is prevalent. Security teams should be aware of this trend in vulnerabilities related to container handling and take proactive measures to strengthen their security posture.

Organizations can enhance their defenses by investing in application security assessments and implementing robust security testing practices.

This vulnerability highlights the importance of continuous monitoring and assessment of security measures in cloud-native environments. The lessons learned from CVE-2025-12970 should inform future development and operational practices.

For further insights on effective security strategies, organizations can explore our resources on vulnerability management programs and the importance of proactive security measures.