CVE-2026-45541: ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a NULL-pointer dereference exists in…

PriorityP343high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.44%

35.1th percentile

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a NULL-pointer dereference exists in the WebSocket subprotocol-negotiation path of the esp_http_server component. While parsing the client-supplied Sec-WebSocket-Protocol request header during the WebSocket handshake, the tokenisation result is dereferenced without a NULL check, so a malformed header value can crash the server before any application-level authentication runs. This issue has been patched in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.

Affected

10 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	—	—
espressif	esp-idf	—	—
espressif	esp-idf	—	—

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