CVE-2025-69209

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Source

https://cve.org/CVERecord?id=CVE-2025-69209

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-69209.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2025-69209

Aliases

GHSA-pvx3-fm7w-6hjm

Downstream

Published

2026-01-21T20:00:41Z

Modified

2026-10-21T02:54:19Z

Severity

6.9 (Medium) CVSS_V4 - 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 CVSS Calculator

Summary

ArduinoCore-avr has Stack-Based Buffer Overflow in WString Float/Double Constructors

Details

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
The Fixing Commit is available at the following link 1a6a417f89c8901dad646efce74ae9d3ddebfd59

References

ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability

Credits

Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)

Database specific

{
    "cna_assigner":  "GitHub_M",
    "cwe_ids":  [
        "CWE-120"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/69xxx/CVE-2025-69209.json"
}

References

Affected packages

Git / github.com/arduino/arduinocore-avr

Affected ranges

Type

GIT

Repo

https://github.com/arduino/arduinocore-avr

Events

Introduced

Fixed

d5d1355b95fd57bbcd30b86db5dc0003440eee8d

Fixed

82a8ad2fb33911d8927c7af22e0472b94325d1a7

Database specific

Show details

{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "0"
                },
                {
                    "fixed":  "1.8.7"
                }
            ],
            "source":  "AFFECTED_FIELD",
            "strategy":  "StringRangeExpression"
        },
        {
            "range":  [
                {
                    "fixed":  "82a8ad2fb33911d8927c7af22e0472b94325d1a7"
                }
            ],
            "source":  "REFERENCES_COMMIT"
        },
        {
            "original_tag":  "1.8.7",
            "range":  [
                {
                    "fixed":  "d5d1355b95fd57bbcd30b86db5dc0003440eee8d"
                }
            ],
            "source":  "REFERENCES_TAG"
        }
    ]
}

Affected versions

1.*

1.6.22

1.6.23

1.8.1

1.8.2

1.8.3

1.8.4

1.8.5

1.8.6

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-69209.json"