CVE-2023-35818: An issue was discovered on Espressif ESP32 3.0 (ESP32

An issue was discovered on Espressif ESP32 3.0 (ESP32_rev300 ROM) devices.

An issue was discovered on Espressif ESP32 3.0 (ESP32_rev300 ROM) devices. An EMFI attack on ECO3 provides the attacker with a capability to influence the PC value at the CPU context level, regardless of Secure Boot and Flash Encryption status. By using this capability, the attacker can exploit another behavior in the chip to gain unauthorized access to the ROM download mode. Access to ROM download mode may be further exploited to read the encrypted flash content in cleartext format or execute stub code.

Description from the National Vulnerability Database, published by MITRE

What it means for a small business

If your business uses Esp32-d0wd-v3 Firmware, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.22%, higher than 12% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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