CVE-2026-48490
Severity CVSS v4.0:
MEDIUM
Type:
CWE-120
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Publication date:
11/09/2026
Last modified:
30/09/2026
Description
ArduinoCore-avr contains the source code and configuration files of the Arduino AVR Boards platform. A vulnerability in versions prior to 1.8.8 allows an attacker to trigger a stack-based buffer overflow when concatenating floating-point values of sufficiently large magnitude onto an Arduino String object. By passing values near the extremes of the float or double range to `String::concat(float)`, `String::concat(double)`, `String::operator+=()`, or the `+` operator with a float/double operand, `dtostrf()` writes beyond the fixed-size stack buffer, causing memory corruption and denial of service. Under specific conditions, this could enable arbitrary code execution on AVR-based Arduino boards. The fix is included starting from the `1.8.8 `release.
Impact
Base Score 4.0
6.90
Severity 4.0
MEDIUM