CVE-2026-25790

MEDIUM

Wazuh has Stack-Based Buffer Overflow in Security Configuration Assessment JSON Parser

Title source: cna
STIX 2.1

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. Starting in version 3.9.0 and prior to version 4.14.3, multiple stack-based buffer overflows exist in the Security Configuration Assessment (SCA) decoder (`wazuh-analysisd`). The use of `sprintf` with a floating-point (`%lf`) format specifier on a fixed-size 128-byte buffer allows a remote attacker to overflow the stack. A specially crafted JSON event can trigger this overflow, leading to a denial of service (crash) or potential RCE on the Wazuh manager. The vulnerability is located in `/src/analysisd/decoders/security_configuration_assessment.c`, within the `FillScanInfo` and `FillCheckEventInfo` functions. In multiple locations, a 128-byte buffer (`char value[OS_SIZE_128];`) is allocated on the stack to hold the string representation of a number from a JSON event. The code checks if the number is an integer or a double. If it's a double, it uses `sprintf(value, "%lf", ...)` to perform the conversion. This `sprintf` call is unbounded. If a floating-point number with a large exponent (e.g., `1.0e150`) is provided, `sprintf` will attempt to write its full string representation (a "1" followed by 150 zeros), which is larger than the 128-byte buffer, corrupting the stack. Version 4.14.3 patches the issue.

Scores

CVSS v3 4.9
EPSS 0.0017
EPSS Percentile 38.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-787 CWE-121
Status published
Products (2)
wazuh/wazuh 3.9.0 - 4.14.3
wazuh/wazuh >= 3.9.0, < 4.14.3
Published Mar 17, 2026
Tracked Since Mar 18, 2026