{"id":"CVE-2025-52471","aliases":["EUVD-2025-19059","GHSA-hqhh-cp47-fv5g"],"status":"published","title":"ESP-NOW Integer Underflow Vulnerability Advisory","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.","severity":{"version":"4.0","score":7.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00914,"percentile":0.60435,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-191"],"published":"2025-06-24T19:53:06Z","modified":"2026-10-28T02:30:34Z","products":[{"vendor":"espressif","product":"esp-idf"}],"references":[{"url":"https://github.com/espressif/esp-idf/security/advisories/GHSA-hqhh-cp47-fv5g","tags":["x_refsource_CONFIRM","Patch","Vendor Advisory","advisory"]},{"url":"https://github.com/espressif/esp-idf/commit/b1a379d57430d265a53aca13d59ddfbf2e7ac409","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/c5fc81917805f99e687c81cc56b68dc5df7ef8b5","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/d4dafbdc3572387cd4f9a62b776580bc4ac3bde7","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/d6ec5a52255b17c1d6ef379e89f9de2c379042f8","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/df7757d8279871fa7a2f42ef3962c6c1ec88b8a2","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/edc227c5eaeced999b5212943a9434379f8aad80","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/52xxx/CVE-2025-52471.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-52471","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2025-52471","title":"ESP-NOW Integer Underflow Vulnerability Advisory","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.","status":"published","published":"2025-06-24T19:53:06.066Z","modified":"2025-06-24T20:02:18.529Z","cvss":[{"version":"4.0","score":7.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U","level":"high","assessor":"cna"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:32:31.309974Z"}],"euvd":[{"id":"EUVD-2025-19059","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.","status":"published","published":"2025-06-24T19:53:06Z","modified":"2025-06-24T20:02:18Z","cvss":[{"version":"4.0","score":7.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U","level":"high"}],"updated_at":"2026-11-02T20:32:16.964954Z"}],"nvd":[{"id":"CVE-2025-52471","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.","status":"published","published":"2025-06-24T20:15:26.033Z","modified":"2026-06-17T09:36:33.323Z","cvss":[{"version":"4.0","score":7.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:11:14.091082Z"}],"osv":[{"id":"CVE-2025-52471","title":"ESP-NOW Integer Underflow Vulnerability Advisory","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.","status":"published","published":"2025-06-24T19:53:06.066Z","modified":"2026-10-28T02:30:34.646408733Z","cvss":[{"version":"4.0","score":7.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U","level":"high"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T15:44:50.45326Z"}]}}