{"id":"CVE-2018-18558","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-18558","generatedAt":"2026-10-29T00:48:29.742Z","title":"Insufficient validation of input data in the 2nd stage bootloader allows a physically proximate attacker to bypass secure boot checks and execute arbitrary code, by crafting an application binary that overwrites a bootloader code segment in…","description":"An issue was discovered in Espressif ESP-IDF 2.x and 3.x before 3.0.6 and 3.1.x before 3.1.1. Insufficient validation of input data in the 2nd stage bootloader allows a physically proximate attacker to bypass secure boot checks and execute arbitrary code, by crafting an application binary that overwrites a bootloader code segment in process_segment in components/bootloader_support/src/esp_image_format.c. The attack is effective when the flash encryption feature is not enabled, or if the attacker finds a different vulnerability that allows them to write this binary to flash memory.","published":"2019-05-13T13:29:02.000Z","lastModified":"2026-06-17T01:47:30.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":6.4,"severity":"MEDIUM","vector":"CVSS:3.0/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-20"],"affected":["espressif/esp-idf"],"epss":{"score":0.00393,"percentile":0.33324,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.39%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/espressif/esp-idf/releases","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://www.espressif.com/en/news/Espressif_Product_Security_Advisory_Concerning_Secure_Boot_%28CVE-2018-18558%29","source":"cve@mitre.org"},{"url":"https://github.com/espressif/esp-idf/releases","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.espressif.com/en/news/Espressif_Product_Security_Advisory_Concerning_Secure_Boot_%28CVE-2018-18558%29","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-18558","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}