How severe is CVE-2025-66409?

CVE-2025-66409 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2025-66409 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66409?

CVE-2025-66409 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66409?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-66409 have an EU (EUVD) identifier?

Yes. CVE-2025-66409 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-200284.

When was CVE-2025-66409 published?

CVE-2025-66409 was published on 2025-12-02 and last updated on 2026-06-17.

CVE-2025-66409

CVE-2025-66409 is a critical-severity vulnerability in Espressif Esp-idf with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v4: 2.7
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-200284
Weakness: CWE-125
Affected product: Espressif Esp-idf
Published: 2025-12-02
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2025-66409?: 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.
How severe is CVE-2025-66409?: CVE-2025-66409 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2025-66409 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66409?: CVE-2025-66409 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66409?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-66409 have an EU (EUVD) identifier?: Yes. CVE-2025-66409 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-200284.
When was CVE-2025-66409 published?: CVE-2025-66409 was published on 2025-12-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:*

More vulnerabilities in Espressif Esp-idf

CVE-2025-52471 — Critical (CVSS 9.8): ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. An integer underflow vulnerability has been…
CVE-2026-45328 — Critical (CVSS 9.3): ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.4 and 6.0, the esp_tee…
CVE-2025-55297 — High (CVSS 8.8): ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. The BluFi example bundled in ESP-IDF was…
CVE-2024-53406 — High (CVSS 8.8): Espressif Esp idf v5.3.0 is vulnerable to Insecure Permissions resulting in Authentication bypass. In the reconnection…
CVE-2021-28139 — High (CVSS 8.8): The Bluetooth Classic implementation in Espressif ESP-IDF 4.4 and earlier does not properly restrict the Feature Page…
CVE-2025-68473 — High (CVSS 8.6): ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.1, 5.4.3, 5.3.4, 5.2.6, 5.1.6,…

All CVEs affecting Espressif Esp-idf →

Other CWE-125 (Out-of-bounds Read) vulnerabilities

CVE-2026-24826 — Critical (CVSS 10.0): Out-of-bounds Write, Divide By Zero, NULL Pointer Dereference, Use of Uninitialized Resource, Out-of-bounds Read,…
CVE-2024-22004 — Critical (CVSS 10.0): Due to length check, an attacker with privilege access on a Linux Nonsecure operating system can trigger a…
CVE-2021-41556 — Critical (CVSS 10.0): sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that…
CVE-2021-21777 — Critical (CVSS 10.0): An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer…
CVE-2017-14451 — Critical (CVSS 10.0): An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A…
CVE-2013-0767 — Critical (CVSS 10.0): The nsSVGPathElement::GetPathLengthScale function in Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and…

Browse all CWE-125 (Out-of-bounds Read) vulnerabilities →