CVE-2025-52471: ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. An integer underflow vulnerability has been identified in the ESP-NOW protocol…

PriorityP261critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

0.74%

50.0th percentile

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. An integer underflow vulnerability has been identified in the ESP-NOW protocol implementation within the ESP Wi-Fi component of versions 5.4.1, 5.3.3, 5.2.5, and 5.1.6 of the ESP-IDF framework. This issue stems from insufficient validation of user-supplied data length in the packet receive function. Under certain conditions, this may lead to out-of-bounds memory access and may allow arbitrary memory write operations. On systems without a memory protection scheme, this behavior could potentially be used to achieve remote code execution (RCE) on the target device. In versions 5.4.2, 5.3.4, 5.2.6, and 5.1.6, ESP-NOW has added more comprehensive validation logic on user-supplied data length during packet reception to prevent integer underflow caused by negative value calculations. For ESP-IDF v5.3 and earlier, a workaround can be applied by validating that the `data_len` parameter received in the RX callback (registered via `esp_now_register_recv_cb()`) is a positive value before further processing. For ESP-IDF v5.4 and later, no application-level workaround is available. Users are advised to upgrade to a patched version of ESP-IDF to take advantage of the built-in mitigation.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv4.07.2HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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