CVE-2026-25790 Wazuh has Stack-Based Buffer Overflow in Security Configuration Assessment JSON Parser
Remote attackers can trigger stack-based buffer overflows in Wazuh's SCA decoder via crafted JSON, causing crashes or potential remote code execution.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-25790?
CVE-2026-25790 is a medium-severity memory corruption vulnerability in Wazuh Wazuh, published on 17 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-25790?
It affects 1 product.
Products include Wazuh Wazuh.
How do I fix CVE-2026-25790?
No fix has been published for CVE-2026-25790 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-25790 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25790 exists.
Other vulnerabilities in Wazuh Wazuh
- CVE-2025-24016 Wazuh Server Deserialization of Untrusted Data
- CVE-2024-32038 Wazuh Analysis Engine Event Decoder Heap-based Buffer Overflow Remote Code Execution Vulnerability
- CVE-2021-44079 Command injection in n/a
- CVE-2024-1243 Remote code execution and local privilege escalation in Wazuh Windows agent via NetNTLMv2 hash theft
- CVE-2026-61800 Wazuh cluster worker file sync allows arbitrary file write under /var/ossec (incomplete fix for CVE-2026-30893)
Sources
Also known as GHSA-cf24-hq8x-5jx2.