ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In 5.5.1, 5.4.3, 5.3.4, 5.2.6, 5.1.6, and earlier, when AVRCP is enabled on ESP32, receiving a malformed VENDOR DEPENDENT command from a peer device can cause the Bluetooth stack to access memory before validating the command buffer length. This may lead to an out-of-bounds read, potentially exposing unintended memory content or causing unexpected behavior.
Conclusion & alert: CVE-2025-66409 is rated Low Risk (17.8/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.07%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-12 | 0.05% | 0.07% | +0.02% |
| 2 | 2026-04-30 | 0.05% | 0.05% | -0.00% |
| 3 | 2025-12-03 | — | 0.05% | — |
Full EPSS history (3 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 2.7 | 4.0 | LOW |
|
— | — | [email protected] |
| 9.1 | 3.1 | CRITICAL |
|
3.9 | 5.2 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| espressif | esp-idf | <= 5.1.6 | cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:* |
| espressif | esp-idf | >= 5.2, <= 5.2.6 | cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:* |
| espressif | esp-idf | >= 5.3, <= 5.3.4 | cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:* |
| espressif | esp-idf | >= 5.4, <= 5.4.3 | cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:* |
| espressif | esp-idf | >= 5.5, <= 5.5.1 | cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:* |