{"vulnerability": "CVE-2026-42854", "sightings": [{"uuid": "44d91974-7ac2-449f-b12f-fbdb62fe013f", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "cve-2026-42854", "type": "seen", "source": "https://bsky.app/profile/offseq.bsky.social/post/3mlpcre43d72l", "content": "CRITICAL stack buffer overflow found in arduino-esp32 (<3.3.8) \u2014 attackers can trigger device crash or RCE via HTTP multipart boundary. Upgrade to 3.3.8 now. https://radar.offseq.com/threat/cve-2026-42854-cwe-121-stack-based-buffer-overflow-caa5555e #OffSeq #IoTSecurity #CVE202642854", "creation_timestamp": "2026-05-13T03:00:30.504482Z"}, {"uuid": "dc607c03-39bf-4114-a911-379dec265df1", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "cve-2026-42854", "type": "seen", "source": "https://infosec.exchange/users/offseq/statuses/116565031474718182", "content": "\ud83d\udd25 CRITICAL: CVE-2026-42854 in arduino-esp32 (<3.3.8) enables stack buffer overflow via HTTP multipart boundary \u2014 can crash device or allow RCE. Patch ASAP by upgrading to 3.3.8! https://radar.offseq.com/threat/cve-2026-42854-cwe-121-stack-based-buffer-overflow-caa5555e #OffSeq #CVE202642854 #IoTSecurity #Espressif", "creation_timestamp": "2026-05-13T03:00:46.708605Z"}, {"uuid": "3b24aea0-0557-4959-96c4-0a503f44e9e6", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-42854", "type": "seen", "source": "https://bsky.app/profile/cyberhub.blog/post/3mmgeqogqkp25", "content": "\ud83d\udccc CVE-2026-42854 - 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 mu... https://www.cyberhub.blog/cves/CVE-2026-42854", "creation_timestamp": "2026-05-22T07:07:08.709118Z"}, {"uuid": "258a1784-cfd1-4df3-8279-077b8258a824", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-42854", "type": "seen", "source": "https://t.me/shimiscyberworld/1430", "content": "\ud83d\udee1\ufe0f SCW \u2502 Critical Vulnerability\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\n\n\u26a0\ufe0f CVE-2026-42854 \u2014 CVSS 9.8\nCVE-2026-42854: Critical RCE in arduino-esp32 WebServer\n\nCVE-2026-42854 \u2014 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 \n\n\ud83d\udd34 Critical \u00b7 3 ATT&CK techniques mapped\n\n#cve  #critical  #high_severity\n\n\ud83d\udcd6 Full analysis + IOCs \u2192\n\ud83c\udfaf Type /detect cve-2026-42854 in the bot\nOpen Intel Bot \u2192\n\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\n\ud83c\udf10 @shimiscyberworld \u00b7 shimiscyberworld.com", "creation_timestamp": "2026-09-12T10:00:05.514391Z"}, {"uuid": "af9b5afc-d1e3-4924-8f43-e59d471558c6", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-42854", "type": "seen", "source": "https://t.me/shimiscyberworld/1430", "content": "\ud83d\udee1\ufe0f SCW \u2502 Critical Vulnerability\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\n\n\u26a0\ufe0f CVE-2026-42854 \u2014 CVSS 9.8\nCVE-2026-42854: Critical RCE in arduino-esp32 WebServer\n\nCVE-2026-42854 \u2014 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 \n\n\ud83d\udd34 Critical \u00b7 3 ATT&CK techniques mapped\n\n#cve  #critical  #high_severity\n\n\ud83d\udcd6 Full analysis + IOCs \u2192\n\ud83c\udfaf Type /detect cve-2026-42854 in the bot\nOpen Intel Bot \u2192\n\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\n\ud83c\udf10 @shimiscyberworld \u00b7 shimiscyberworld.com", "creation_timestamp": "2026-09-13T00:00:55.948946Z"}]}