Buffer overflow in Espressif Arduino-Esp32
CVE-2026-41429
arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, there is a remotely reachable memory corruption issue in the NBNS packet handling path. When NetBIOS is enabled by calling NBNS.begin(...), the device listens on UDP port 137 and processes untrusted NBNS requests from the local network. The request parser trusts the attacker-controlled name_len field without enforcing a bound consistent with the fixed-size destination buffers used later in the flow. This vulnerability is fixed in 3.3.8.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (24.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
Weakness classification (CWE)
References
- github.com/espressif/arduino-esp32/security/advisories/GHSA-92j9-c75g-2c5f (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-41429?
- CVE-2026-41429 is a high-severity vulnerability in Espressif Arduino-Esp32, classified under Stack-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-04-24.
- How severe is CVE-2026-41429?
- High severity. CVSS v3 base score is 8.8 out of 10.