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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-69209 Detail

Description

ArduinoCore-avr contains the source code and configuration files of the Arduino AVR Boards platform. A vulnerability in versions prior to 1.8.7 allows an attacker to trigger a stack-based buffer overflow when converting floating-point values to strings with high precision. By passing very large `decimalPlaces` values to the affected String constructors or concat methods, the `dtostrf` function writes beyond fixed-size stack buffers, causing memory corruption and denial of service. Under specific conditions, this could enable arbitrary code execution on AVR-based Arduino boards. ### Patches - The Fix is included starting from the `1.8.7` release available from the following link [ArduinoCore-avr v1.8.7](https://github.com/arduino/ArduinoCore-avr) - The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59) ### References - [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX) ### Credits - Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 6.9 MEDIUM
Vector:  CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/arduino/ArduinoCore-avr/commit/82a8ad2fb33911d8927c7af22e0472b94325d1a7 GitHub, Inc.
https://github.com/arduino/ArduinoCore-avr/pull/613 GitHub, Inc.
https://github.com/arduino/ArduinoCore-avr/releases/tag/1.8.7 GitHub, Inc.
https://github.com/arduino/ArduinoCore-avr/security/advisories/GHSA-pvx3-fm7w-6hjm GitHub, Inc.
https://support.arduino.cc/hc/en-us/articles/24985906702748-ASEC-26-001-ArduinoCore-AVR-v1-8-7-Resolves-Stack-Based-Buffer-Overflow-Vulnerability GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-69209
NVD Published Date:
01/21/2026
NVD Last Modified:
01/21/2026
Source:
GitHub, Inc.