CVE-2026-25790CWE-121CWE-787

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

Medium · published March 17, 2026

CVSS v3.1
4.9
EPSS
1%
Percentile
48.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00602 · 48.1th percentile
Weaknesses
CWE-121 · Stack-based Buffer Overflow; CWE-787 · Out-of-bounds Write
Published
2026-03-17T18:41Z
EPSS history
Timeline
  • 17 MAR 18:41Z
    Wazuh has Stack-Based Buffer Overflow in Security Configuration Assessment JSON Parser
    cvelistv5