espressif esp-idf up to 6.0 null pointer dereference

Summaryinfo

A vulnerability classified as problematic has been found in espressif esp-idf 5.2.6/5.3.5/5.4.4/5.5.4/6.0. Affected by this issue is some unknown functionality. The manipulation leads to null pointer dereference. This vulnerability is traded as CVE-2026-45541. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in espressif esp-idf 5.2.6/5.3.5/5.4.4/5.5.4/6.0. This issue affects some unknown processing. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-45541 since 05/12/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 5.2.6, 5.2.7, 5.3.5, 5.3.6, 5.4.4, 5.4.5, 5.5.4, 5.5.5, 6.0 or 6.0.1 eliminates this vulnerability. Applying the patch 00a2f7fbbbd8fe6d04729022e1d5c9a49435bfe8 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Vendor

• espressif

Name

• esp-idf

Version

• 5.2.6
• 5.3.5
• 5.4.4
• 5.5.4
• 6.0

License

• open-source

Website

• Product: https://github.com/espressif/esp-idf/

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