Physical flash disclosure and code execution via EMFI
Published Jul 17, 2023 · Updated Oct 31, 2024
Fault injection in Espressif ESP32 revisions 3.0 and 3.1 allows physically proximate attackers to read flash data or execute stub code. A precisely timed electromagnetic pulse corrupts a computed flash value loaded into the CPU program counter, redirecting execution into the unhardened ROM UART download-mode entry point. Exploitation requires physical chip access, sophisticated EMFI equipment, repeated spatial and timing calibration, and flash manipulation; successful access exposes decrypted flash contents or permits code execution in internal memory.
Summary
What happened
Fault injection in Espressif ESP32 revisions 3.0 and 3.1 allows physically proximate attackers to read flash data or execute stub code. A precisely timed electromagnetic pulse corrupts a computed flash value loaded into the CPU program counter, redirecting execution into the unhardened ROM UART download-mode entry point. Exploitation requires physical chip access, sophisticated EMFI equipment, repeated spatial and timing calibration, and flash manipulation; successful access exposes decrypted flash contents or permits code execution in internal memory.
The record
- CVE
- CVE-2023-35818
- Published
- Jul 17, 2023
- Updated
- Oct 31, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- Unavailable
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 17, 2023CVE publishedPublication date reported by the CVE source.
- Oct 31, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
- Breaking Espressif’s ESP32 V3: Program Counter Control with Computed Values using Fault Injectionproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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