CVE-2026-45541: CWE-476: NULL Pointer Dereference in espressif esp-idf
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.
AI Analysis
Technical Summary
The Espressif esp-idf framework versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0 contain a NULL-pointer dereference vulnerability (CWE-476) in the WebSocket subprotocol-negotiation path of the esp_http_server component. Specifically, the tokenization of the client-supplied Sec-WebSocket-Protocol header during the WebSocket handshake lacks a NULL check before dereferencing, which can lead to a server crash. This issue is addressed in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.
Potential Impact
Successful exploitation of this vulnerability can cause a denial of service by crashing the server before any application-level authentication occurs. There is no impact on confidentiality or integrity reported. The CVSS score is 7.5 (high), reflecting the potential for service disruption without requiring privileges or user interaction.
Mitigation Recommendations
A fix is available in esp-idf versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1. Users should upgrade to these patched versions to remediate the vulnerability. No alternative mitigations are specified.
CVE-2026-45541: CWE-476: NULL Pointer Dereference in espressif esp-idf
Description
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.
CVSS v3.1
Score 7.5high
Affected software
pkg:github/espressif/esp-idfRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Espressif esp-idf framework versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0 contain a NULL-pointer dereference vulnerability (CWE-476) in the WebSocket subprotocol-negotiation path of the esp_http_server component. Specifically, the tokenization of the client-supplied Sec-WebSocket-Protocol header during the WebSocket handshake lacks a NULL check before dereferencing, which can lead to a server crash. This issue is addressed in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.
Potential Impact
Successful exploitation of this vulnerability can cause a denial of service by crashing the server before any application-level authentication occurs. There is no impact on confidentiality or integrity reported. The CVSS score is 7.5 (high), reflecting the potential for service disruption without requiring privileges or user interaction.
Mitigation Recommendations
A fix is available in esp-idf versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1. Users should upgrade to these patched versions to remediate the vulnerability. No alternative mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-12T17:48:47.878Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a28c09e8dd33fbd85c1ae6b
Added to database: 06/10/2026, 01:40:46 UTC
Last enriched: 06/17/2026, 08:55:41 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 60
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