CVE-2025-52471 ESP-NOW Integer Underflow Vulnerability Advisory
An integer underflow in ESP-IDF's ESP-NOW protocol allows remote attackers to execute arbitrary code on IoT devices via crafted packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-52471?
CVE-2025-52471 is a high-severity vulnerability in espressif esp-idf, published on 24 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. An integer underflow vulnerability has been identified in the ESP-NOW protocol implementation within the ESP Wi-Fi component of versions 5.4.1, 5.3.3, 5.2.5, and 5.1.6 of the ESP-IDF framework. This issue stems from insufficient validation of user-supplied data length in the packet receive function. Under certain conditions, this may lead to out-of-bounds memory access and may allow arbitrary memory write operations. On systems without a memory protection scheme, this behavior could potentially be used to achieve remote code execution (RCE) on the target device. In versions 5.4.2, 5.3.4, 5.2.6, and 5.1.6, ESP-NOW has added more comprehensive validation logic on user-supplied data length during packet reception to prevent integer underflow caused by negative value calculations. For ESP-IDF v5.3 and earlier, a workaround can be applied by validating that the `data_len` parameter received in the RX callback (registered via `esp_now_register_recv_cb()`) is a positive value before further processing. For ESP-IDF v5.4 and later, no application-level workaround is available. Users are advised to upgrade to a patched version of ESP-IDF to take advantage of the built-in mitigation.
Weakness: CWE-191
Which versions are affected by CVE-2025-52471?
It affects 1 product.
Products include Espressif Esp-Idf.
How do I fix CVE-2025-52471?
No fix has been published for CVE-2025-52471 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-52471 being exploited?
There is no known exploitation of CVE-2025-52471 in the wild and no public exploit code.
Other vulnerabilities in espressif esp-idf
Sources
Also known as GHSA-hqhh-cp47-fv5g.