Medium 6.3Published Feb 4, 2026

CVE-2026-25532ESF-IDF is Vulnerable to WPS Enrollee Fragment Integer Underflow

Updated under an hour ago (Oct 27, 2026, 3:00 AM ET)

Does this affect you?

It affects espressif esp-idf and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for espressif esp-idf

Exploited in the last 30 days

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.

CVSS: 6.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Weakness (CWE): CWE-191
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Feb 4, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

espressif esp-idf espressif:esp_idf (from the name)	= 5.5.2; = 5.4.3; = 5.3.4; = 5.2.6; = 5.1.6	CNA record
espressif esp-idf espressif:esp-idf	5.1.6; 5.2.6; 5.3.4; 5.4.3; 5.5.2	NVD

References

References

https://github.com/espressif/esp-idf/security/advisories/GHSA-m2h2-683f-9mw7	x-refsource-confirm, patch, third-party-advisory
https://github.com/espressif/esp-idf/commit/60f992a26de17bb5406f2149a2f8282dd7ad1c59	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/6f6766f917bc940ffbcc97eac4765a6ab15d5f79	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/73a587d42a57ece1962b6a4c530b574600650f63	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/b209fae993d795255827ce6b2b0d6942a377f5d4	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/b88befde6b5addcdd8d7373ce55c8052dea1e855	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/cad36beb4cde27abcf316cd90d8d8dddbc6f213a	x-refsource-misc, patch
https://github.com/espressif/esp-idf/commit/de28801e8ea6a736b6f0db6fc0c682739363bb41	x-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.