{"id":"CVE-2026-25532","aliases":["EUVD-2026-5376","GHSA-m2h2-683f-9mw7"],"status":"published","title":"ESF-IDF is Vulnerable to WPS Enrollee Fragment Integer Underflow","description":"ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.2, 5.4.3, 5.3.4, 5.2.6, and 5.1.6, a vulnerability exists in the WPS (Wi-Fi Protected Setup) Enrollee implementation where malformed EAP-WSC packets with truncated payloads can cause integer underflow during fragment length calculation. When processing EAP-Expanded (WSC) messages, the code computes frag_len by subtracting header sizes from the total packet length. If an attacker sends a packet where the EAP Length field covers only the header and flags but omits the expected payload (such as the 2-byte Message Length field when WPS_MSG_FLAG_LEN is set), frag_len becomes negative. This negative value is then implicitly cast to size_t when passed to wpabuf_put_data(), resulting in a very large unsigned value. This issue has been patched in versions 5.5.3, 5.4.4, 5.3.5, 5.2.7, and 5.1.7.","severity":{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00248,"percentile":0.16227,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-191"],"published":"2026-02-04T17:58:08Z","modified":"2026-10-28T10:51:23Z","products":[{"vendor":"espressif","product":"esp-idf"}],"references":[{"url":"https://github.com/espressif/esp-idf/security/advisories/GHSA-m2h2-683f-9mw7","tags":["x_refsource_CONFIRM","Patch","Third Party Advisory","advisory"]},{"url":"https://github.com/espressif/esp-idf/commit/60f992a26de17bb5406f2149a2f8282dd7ad1c59","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/6f6766f917bc940ffbcc97eac4765a6ab15d5f79","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/73a587d42a57ece1962b6a4c530b574600650f63","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/b209fae993d795255827ce6b2b0d6942a377f5d4","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/b88befde6b5addcdd8d7373ce55c8052dea1e855","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/cad36beb4cde27abcf316cd90d8d8dddbc6f213a","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/espressif/esp-idf/commit/de28801e8ea6a736b6f0db6fc0c682739363bb41","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25532.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25532","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-25532","title":"ESF-IDF is Vulnerable to WPS Enrollee Fragment Integer Underflow","description":"ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.2, 5.4.3, 5.3.4, 5.2.6, and 5.1.6, a vulnerability exists in the WPS (Wi-Fi Protected Setup) Enrollee implementation where malformed EAP-WSC packets with truncated payloads can cause integer underflow during fragment length calculation. When processing EAP-Expanded (WSC) messages, the code computes frag_len by subtracting header sizes from the total packet length. If an attacker sends a packet where the EAP Length field covers only the header and flags but omits the expected payload (such as the 2-byte Message Length field when WPS_MSG_FLAG_LEN is set), frag_len becomes negative. This negative value is then implicitly cast to size_t when passed to wpabuf_put_data(), resulting in a very large unsigned value. This issue has been patched in versions 5.5.3, 5.4.4, 5.3.5, 5.2.7, and 5.1.7.","status":"published","published":"2026-02-04T17:58:08.1Z","modified":"2026-02-04T19:24:47.749Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T13:41:19.694734Z"}],"euvd":[{"id":"EUVD-2026-5376","description":"ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.2, 5.4.3, 5.3.4, 5.2.6, and 5.1.6, a vulnerability exists in the WPS (Wi-Fi Protected Setup) Enrollee implementation where malformed EAP-WSC packets with truncated payloads can cause integer underflow during fragment length calculation. When processing EAP-Expanded (WSC) messages, the code computes frag_len by subtracting header sizes from the total packet length. If an attacker sends a packet where the EAP Length field covers only the header and flags but omits the expected payload (such as the 2-byte Message Length field when WPS_MSG_FLAG_LEN is set), frag_len becomes negative. This negative value is then implicitly cast to size_t when passed to wpabuf_put_data(), resulting in a very large unsigned value. This issue has been patched in versions 5.5.3, 5.4.4, 5.3.5, 5.2.7, and 5.1.7.","status":"published","published":"2026-02-04T17:58:08Z","modified":"2026-02-04T19:24:47Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","level":"medium"}],"updated_at":"2026-11-02T19:48:44.193176Z"}],"nvd":[{"id":"CVE-2026-25532","description":"ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.2, 5.4.3, 5.3.4, 5.2.6, and 5.1.6, a vulnerability exists in the WPS (Wi-Fi Protected Setup) Enrollee implementation where malformed EAP-WSC packets with truncated payloads can cause integer underflow during fragment length calculation. When processing EAP-Expanded (WSC) messages, the code computes frag_len by subtracting header sizes from the total packet length. If an attacker sends a packet where the EAP Length field covers only the header and flags but omits the expected payload (such as the 2-byte Message Length field when WPS_MSG_FLAG_LEN is set), frag_len becomes negative. This negative value is then implicitly cast to size_t when passed to wpabuf_put_data(), resulting in a very large unsigned value. This issue has been patched in versions 5.5.3, 5.4.4, 5.3.5, 5.2.7, and 5.1.7.","status":"published","published":"2026-02-04T18:16:09.747Z","modified":"2026-06-17T10:24:48.313Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T14:12:05.149641Z"}],"osv":[{"id":"CVE-2026-25532","title":"ESF-IDF is Vulnerable to WPS Enrollee Fragment Integer Underflow","description":"ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.5.2, 5.4.3, 5.3.4, 5.2.6, and 5.1.6, a vulnerability exists in the WPS (Wi-Fi Protected Setup) Enrollee implementation where malformed EAP-WSC packets with truncated payloads can cause integer underflow during fragment length calculation. When processing EAP-Expanded (WSC) messages, the code computes frag_len by subtracting header sizes from the total packet length. If an attacker sends a packet where the EAP Length field covers only the header and flags but omits the expected payload (such as the 2-byte Message Length field when WPS_MSG_FLAG_LEN is set), frag_len becomes negative. This negative value is then implicitly cast to size_t when passed to wpabuf_put_data(), resulting in a very large unsigned value. This issue has been patched in versions 5.5.3, 5.4.4, 5.3.5, 5.2.7, and 5.1.7.","status":"published","published":"2026-02-04T17:58:08.1Z","modified":"2026-10-28T10:51:23.421568841Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H","level":"medium"}],"cwes":["CWE-191"],"updated_at":"2026-11-02T15:44:59.438965Z"}]}}