{"id":"CVE-2025-69209","aliases":["DEBIAN-CVE-2025-69209","EUVD-2025-206313","GHSA-pvx3-fm7w-6hjm","UBUNTU-CVE-2025-69209"],"status":"published","title":"ArduinoCore-avr has Stack-Based Buffer Overflow in WString Float/Double Constructors","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.\n\n### Patches\n\n- 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)\n\n- The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59)\n\n### References\n\n- [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX)\n\n### Credits\n\n- Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)","severity":{"version":"4.0","score":6.9,"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","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00177,"percentile":0.07269,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-120"],"published":"2026-01-21T20:00:41Z","modified":"2026-10-28T02:30:49Z","fixes":[{"ecosystem":"Debian:12","package":"arduino-core-avr","fixed_in":["1.8.7+dfsg-1~deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"arduino-core-avr","fixed_in":["1.8.7+dfsg-1~deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"arduino-core-avr","fixed_in":["1.8.7+dfsg-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.7+dfsg-1~deb12u1"}]}],"versions":["1.8.6+dfsg-1","1.8.6+dfsg-2"]},{"source":"osv","ecosystem":"Debian:13","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.7+dfsg-1~deb13u1"}]}],"versions":["1.8.6+dfsg-2","1.8.7+dfsg-1~deb12u1"]},{"source":"osv","ecosystem":"Debian:14","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.7+dfsg-1"}]}],"versions":["1.8.6+dfsg-2","1.8.7+dfsg-1~deb12u1","1.8.7+dfsg-1~deb13u1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.3+dfsg1-1","1.8.4+dfsg1-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"arduino-core-avr","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.6+dfsg-1"]}],"products":[{"vendor":"arduino","product":"arduinocore-avr"}],"references":[{"url":"https://github.com/arduino/ArduinoCore-avr/security/advisories/GHSA-pvx3-fm7w-6hjm","tags":["x_refsource_CONFIRM","advisory","report"]},{"url":"https://github.com/arduino/ArduinoCore-avr/pull/613","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/arduino/ArduinoCore-avr/commit/82a8ad2fb33911d8927c7af22e0472b94325d1a7","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/arduino/ArduinoCore-avr/releases/tag/1.8.7","tags":["x_refsource_MISC","web","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","tags":["x_refsource_MISC","web","report"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/69xxx/CVE-2025-69209.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-69209","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2025-69209","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-69209","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-69209","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2025-69209","title":"ArduinoCore-avr has Stack-Based Buffer Overflow in WString Float/Double Constructors","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.\n\n### Patches\n\n- 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)\n\n- The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59)\n\n### References\n\n- [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX)\n\n### Credits\n\n- Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)","status":"published","published":"2026-01-21T20:00:41.026Z","modified":"2026-01-21T21:28:52.505Z","cvss":[{"version":"4.0","score":6.9,"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","level":"medium","assessor":"cna"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:32:40.774223Z"}],"euvd":[{"id":"EUVD-2025-206313","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.\n\n### Patches\n\n- 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)\n\n- The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59)\n\n### References\n\n- [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX)\n\n### Credits\n\n- Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)","status":"published","published":"2026-01-21T20:00:41Z","modified":"2026-01-21T21:28:52Z","cvss":[{"version":"4.0","score":6.9,"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","level":"medium"}],"updated_at":"2026-11-02T19:48:48.974823Z"}],"nvd":[{"id":"CVE-2025-69209","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.\n\n### Patches\n\n- 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)\n\n- The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59)\n\n### References\n\n- [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX)\n\n### Credits\n\n- Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)","status":"published","published":"2026-01-21T20:16:10.28Z","modified":"2026-06-17T10:00:17.547Z","cvss":[{"version":"4.0","score":6.9,"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:11:57.915063Z"}],"osv":[{"id":"CVE-2025-69209","title":"ArduinoCore-avr has Stack-Based Buffer Overflow in WString Float/Double Constructors","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.\n\n### Patches\n\n- 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)\n\n- The Fixing Commit is available at the following link [1a6a417f89c8901dad646efce74ae9d3ddebfd59](https://github.com/arduino/ArduinoCore-avr/pull/613/commits/1a6a417f89c8901dad646efce74ae9d3ddebfd59)\n\n### References\n\n- [ASEC-26-001 ArduinoCore-avr vXXXX Resolves Buffer Overflow Vulnerability](https://support.arduino.cc/hc/en-us/articles/XXXXX)\n\n### Credits\n\n- Maxime Rossi Bellom and Ramtine Tofighi Shirazi from SecMate (https://secmate.dev/)","status":"published","published":"2026-01-21T20:00:41.026Z","modified":"2026-10-28T02:30:49.835734921Z","cvss":[{"version":"4.0","score":6.9,"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","level":"medium"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T15:44:52.859856Z"},{"id":"DEBIAN-CVE-2025-69209","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/)","status":"published","published":"2026-01-21T20:16:10.28Z","modified":"2026-09-01T20:05:58.344253448Z","cvss":[{"version":"4.0","score":6.9,"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-02T15:45:48.025964Z"},{"id":"UBUNTU-CVE-2025-69209","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/)","status":"published","published":"2026-01-21T20:16:00Z","modified":"2026-10-17T12:57:40.883982224Z","cvss":[{"version":"4.0","score":6.9,"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","level":"medium"}],"updated_at":"2026-11-02T16:55:55.926217Z"}]}}