Fluent Bit up to 3.0.3 Embedded HTTP Server heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability was found in Fluent Bit up to 3.0.3 and classified as very critical. Affected by this issue is an unknown functionality of the component Embedded HTTP Server. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

A memory corruption vulnerability in Fluent Bit versions 2.0.7 thru 3.0.3. This issue lies in the embedded http server’s parsing of trace requests and may result in denial of service conditions, information disclosure, or remote code execution.

The advisory is shared for download at tenable.com. This vulnerability is handled as CVE-2024-4323 since 04/29/2024. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/20/2024).

Applying the patch 9311b43a258352797af40749ab31a63c32acfd04 is able to eliminate this problem. The bugfix is ready for download at github.com.

Similar entries are available at VDB-19109, VDB-19507, VDB-31956 and VDB-41035.





CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔒
VulDB CVSS-BT Score: 🔒
VulDB Vector: 🔒
VulDB Reliability: 🔍


VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.6

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (Tenable Network Security, Inc.): 🔒



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Heap-based overflow
CWE: CWE-122 / CWE-119

Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 9311b43a258352797af40749ab31a63c32acfd04


04/29/2024 CVE reserved
05/20/2024 +21 days Advisory disclosed
05/20/2024 +0 days VulDB entry created
05/20/2024 +0 days VulDB entry last update


Advisory: tenable.com
Status: Confirmed

CVE: CVE-2024-4323 (🔒)
See also: 🔒


Created: 05/20/2024 03:56 PM
Changes: 05/20/2024 03:56 PM (64)
Complete: 🔍
Cache ID: 44:8BE:40


Anonymous User 👤 (+0)
2 months ago
Good morning.
Are you aware of which architecture and/or operating system are functional for code execution? From the analysis of tenable it is not clear.
Best Regards,
We assume that it affects all supported platforms.
Anonymous User 👤 (+0)
2 months ago
OK, Thank very much.

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