{"id":"UBUNTU-CVE-2025-69209","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](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/)","modified":"2026-05-20T16:23:49.186604208Z","published":"2026-01-21T20:16:00Z","upstream":["CVE-2025-69209"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-69209"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2025-69209"},{"type":"REPORT","url":"https://github.com/arduino/ArduinoCore-avr/security/advisories/GHSA-pvx3-fm7w-6hjm"},{"type":"REPORT","url":"https://github.com/arduino/ArduinoCore-avr/pull/613"},{"type":"REPORT","url":"https://support.arduino.cc/hc/en-us/articles/24985906702748-ASEC-26-001-ArduinoCore-AVR-v1-8-7-Resolves-Stack-Based-Buffer-Overflow-Vulnerability"},{"type":"REPORT","url":"https://github.com/arduino/ArduinoCore-avr/commit/82a8ad2fb33911d8927c7af22e0472b94325d1a7"},{"type":"REPORT","url":"https://github.com/arduino/ArduinoCore-avr/releases/tag/1.8.7"}],"affected":[{"package":{"name":"arduino-core-avr","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/arduino-core-avr?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.3+dfsg1-1","1.8.4+dfsg1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"arduino-core-avr","binary_version":"1.8.4+dfsg1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-69209.json"}},{"package":{"name":"arduino-core-avr","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/arduino-core-avr?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"arduino-core-avr","binary_version":"1.8.6+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-69209.json"}},{"package":{"name":"arduino-core-avr","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/arduino-core-avr?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.8.6+dfsg-1","binary_name":"arduino-core-avr"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-69209.json"}},{"package":{"name":"arduino-core-avr","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/arduino-core-avr?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"arduino-core-avr","binary_version":"1.8.6+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-69209.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"},{"type":"Ubuntu","score":"medium"}]}