arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, the WebServer multipart form parser in arduino-esp32 allocates a Variable Length Array (VLA) on the stack whose size is derived from an attacker-controlled HTTP header field (Content-Type: multipart/form-data; boundary=...) without enforcing any length limit. Sending a boundary string longer than ~8000 characters overflows the 8192-byte task stack of the loopTask, causing a crash and potential remote code execution. This vulnerability is fixed in 3.3.8.
References
| Link | Resource |
|---|---|
| https://github.com/espressif/arduino-esp32/security/advisories/GHSA-8cmm-3887-r32j | Exploit Vendor Advisory |
| https://github.com/espressif/arduino-esp32/security/advisories/GHSA-8cmm-3887-r32j | Exploit Vendor Advisory |
Configurations
History
18 May 2026, 13:09
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:espressif:arduino-esp32:*:-:*:*:*:*:*:* | |
| References | () https://github.com/espressif/arduino-esp32/security/advisories/GHSA-8cmm-3887-r32j - Exploit, Vendor Advisory | |
| First Time |
Espressif arduino-esp32
Espressif |
13 May 2026, 16:16
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://github.com/espressif/arduino-esp32/security/advisories/GHSA-8cmm-3887-r32j - |
12 May 2026, 22:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-05-12 22:16
Updated : 2026-05-18 13:09
NVD link : CVE-2026-42854
Mitre link : CVE-2026-42854
CVE.ORG link : CVE-2026-42854
JSON object : View
Products Affected
espressif
- arduino-esp32
CWE
CWE-121
Stack-based Buffer Overflow