CVE-2026-45541 Espressif — Exploit & Vulnerability Details HIGH

Parameter	Value
CVSS	7.5 (HIGH)
Type	CWE-476 (NULL Pointer Dereference)
Vendor	Espressif
Public PoC	No

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.

Attack Parameters

Attack Vector

Network

Can be exploited remotely

Attack Complexity

Low

Easy to exploit

Privileges Required

None

No privileges needed

User Interaction

None

No user interaction needed

Impact Assessment

Confidentiality

None

No data leak

Integrity

None

No data modification

Availability

High

Complete denial of service

CVSS Vector v3.1

Weakness Type (CWE)

CWE-476 NULL Pointer Dereference

Vulnerable Products 5

Configuration	From (including)	Up to (excluding)
Espressif Esp-Idf cpe:2.3:a:espressif:esp-idf:5.2.6:::::::*	—	—
Espressif Esp-Idf cpe:2.3:a:espressif:esp-idf:5.3.5:::::::*	—	—
Espressif Esp-Idf cpe:2.3:a:espressif:esp-idf:5.4.4:::::::*	—	—
Espressif Esp-Idf cpe:2.3:a:espressif:esp-idf:5.5.4:::::::*	—	—
Espressif Esp-Idf cpe:2.3:a:espressif:esp-idf:6.0:::::::*	—	—