CVE-2026-45541
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.44% probability · 37th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- espressif/esp-idf
- Source
- security-advisories@github.com
References
- https://github.com/espressif/esp-idf/commit/00a2f7fbbbd8fe6d04729022e1d5c9a49435bfe8Patch
- https://github.com/espressif/esp-idf/commit/0dc4ee7537f3b12350f5966cecacd59bba840ec6Patch
- https://github.com/espressif/esp-idf/commit/37508ab91124ef426a7396d30f79eba1162700c7Patch
- https://github.com/espressif/esp-idf/commit/9fc0ca13b3b85b98d32b98cd9dc8ff9d82642b7bPatch
- https://github.com/espressif/esp-idf/commit/dc46dc51359749e50617eb70d6f9ae298adc4fffPatch
- https://github.com/espressif/esp-idf/commit/f88a47e4f37fb11ae4b0908cd5c80059d83198c6Patch
- https://github.com/espressif/esp-idf/security/advisories/GHSA-3j8v-xgrq-5vg8Mitigation, Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.