6.3
MEDIUM CVSS 3.1
CVE-2026-25532
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.

INFO

Published Date :

Feb. 4, 2026, 6:16 p.m.

Last Modified :

Feb. 4, 2026, 6:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-25532 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update ESF-IDF to a patched version to fix integer underflow in WPS.
  • Update ESF-IDF to version 5.5.3 or later.
  • Update ESF-IDF to version 5.4.4 or later.
  • Update ESF-IDF to version 5.3.5 or later.
  • Update ESF-IDF to version 5.2.7 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-25532 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-25532 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-25532 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-25532 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Feb. 04, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
    Added CWE CWE-191
    Added Reference https://github.com/espressif/esp-idf/commit/60f992a26de17bb5406f2149a2f8282dd7ad1c59
    Added Reference https://github.com/espressif/esp-idf/commit/6f6766f917bc940ffbcc97eac4765a6ab15d5f79
    Added Reference https://github.com/espressif/esp-idf/commit/73a587d42a57ece1962b6a4c530b574600650f63
    Added Reference https://github.com/espressif/esp-idf/commit/b209fae993d795255827ce6b2b0d6942a377f5d4
    Added Reference https://github.com/espressif/esp-idf/commit/b88befde6b5addcdd8d7373ce55c8052dea1e855
    Added Reference https://github.com/espressif/esp-idf/commit/cad36beb4cde27abcf316cd90d8d8dddbc6f213a
    Added Reference https://github.com/espressif/esp-idf/commit/de28801e8ea6a736b6f0db6fc0c682739363bb41
    Added Reference https://github.com/espressif/esp-idf/security/advisories/GHSA-m2h2-683f-9mw7
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 6.3
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact