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TI-2026-33292 Aliases CVE-2026-45541

ESF-IDF: Remote Null Pointer Dereference in WebSocket Server

Priority LOW 39CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-476.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00439 38th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
espressifesp-idf= 6.0; = 5.5.4; = 5.4.4; = 5.3.5; = 5.2.6—No fix listedCNA
  • esp-idf Vendorespressif Affected = 6.0; = 5.5.4; = 5.4.4; = 5.3.5; = 5.2.6 Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:espressif:esp-idf:5.2.6:*:*:*:*:*:*:*5.2.6Vulnerableespressif
cpe:2.3:a:espressif:esp-idf:5.3.5:*:*:*:*:*:*:*5.3.5Vulnerableespressif
cpe:2.3:a:espressif:esp-idf:5.4.4:*:*:*:*:*:*:*5.4.4Vulnerableespressif
cpe:2.3:a:espressif:esp-idf:5.5.4:*:*:*:*:*:*:*5.5.4Vulnerableespressif
cpe:2.3:a:espressif:esp-idf:6.0:*:*:*:*:*:*:*6.0Vulnerableespressif
  • cpe:2.3:a:espressif:esp-idf:5.2.6:*:*:*:*:*:*:* Versions 5.2.6 Vulnerable ·espressif
  • cpe:2.3:a:espressif:esp-idf:5.3.5:*:*:*:*:*:*:* Versions 5.3.5 Vulnerable ·espressif
  • cpe:2.3:a:espressif:esp-idf:5.4.4:*:*:*:*:*:*:* Versions 5.4.4 Vulnerable ·espressif
  • cpe:2.3:a:espressif:esp-idf:5.5.4:*:*:*:*:*:*:* Versions 5.5.4 Vulnerable ·espressif
  • cpe:2.3:a:espressif:esp-idf:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·espressif

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-45541
  2. 2026-10-25 EPSS moved to the below the 50th percentile
  3. 2026-10-25 Priority changed: MEDIUM → LOW

References

Patch 7

  • TI-2024-22076 Buffer Overflow vulnerability in esp-idf v.5.1 allows a remote attacker to execute… CVSS 3.1MEDIUM 6.5
  • TI-2026-33125 ESF-IDF: Out-of-Bounds Write in ESP-TEE Secure Service Wrappers CVSS 3.1CRITICAL 9.3
  • TI-2025-32598 ESP-NOW Integer Underflow Vulnerability Advisory CVSS 4.0HIGH 7.2
  • TI-2022-08703 Espressif Bluetooth Mesh Stack Vulnerable to Out-of-bounds Write leading to memory buffer corruption CVSS 3.1HIGH 8.8
  • TI-2021-09371 The Bluetooth Classic implementation in Espressif ESP-IDF 4.4 and earlier does not… CVSS 3.1HIGH 8.8
  • TI-2024-35792 Espressif Esp idf v5.3.0 is vulnerable to Insecure Permissions resulting in… CVSS 3.1HIGH 8.8
See all 30 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences