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CVE-2025-69209

MediumCVSS 6.9 / 10
Published Jan 21, 2026·Last modified Apr 10, 2026
Affected Components(0)

No affected components available

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

References

Credits

  • Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)
Risk Scores
Base Score
6.9

The vulnerability requires local access to the device to be exploited. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability.

Threat Intelligence
4.6

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
0.15%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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