CVE-2021-35393

Name: CVE-2021-35393
Creator: NVD / NIST
Published: 2021-08-16T12:15:07.23+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 70.33%

Last modified Jun 17, 2026

CVE-2021-35393 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Realtek Jungle SDK version v2.x up to v3.4.14B provides a 'WiFi Simple Config' server that implements both UPnP and SSDP protocols. The binary is usually named wscd or mini_upnpd and is the successor to miniigd. EPSS estimates a 70.33% chance of exploitation in the next 30 days.

Description

Realtek Jungle SDK version v2.x up to v3.4.14B provides a 'WiFi Simple Config' server that implements both UPnP and SSDP protocols. The binary is usually named wscd or mini_upnpd and is the successor to miniigd. The server is vulnerable to a stack buffer overflow vulnerability that is present due to unsafe parsing of the UPnP SUBSCRIBE/UNSUBSCRIBE Callback header. Successful exploitation of this vulnerability allows remote unauthenticated attackers to gain arbitrary code execution on the affected device.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

70.33%

99.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Realtek	Rtl819x Jungle Software Development Kit	>= 2.0, <= 3.4.14b

References

https://www.iot-inspector.com/blog/advisory-multiple-issues-realtek-sdk-iot-supply-chainBroken Link, Exploit, Third Party Advisory
https://www.realtek.com/en/cu-1-en/cu-1-taiwan-enBroken Link, Patch, Vendor Advisory
https://www.realtek.com/images/safe-report/Realtek_APRouter_SDK_Advisory-CVE-2021-35392_35395.pdfPatch, Vendor Advisory
https://www.iot-inspector.com/blog/advisory-multiple-issues-realtek-sdk-iot-supply-chainBroken Link, Exploit, Third Party Advisory
https://www.realtek.com/en/cu-1-en/cu-1-taiwan-enBroken Link, Patch, Vendor Advisory
https://www.realtek.com/images/safe-report/Realtek_APRouter_SDK_Advisory-CVE-2021-35392_35395.pdfPatch, Vendor Advisory

Timeline

Published: Aug 16, 2021
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-35393?

How severe is CVE-2021-35393?

CVE-2021-35393 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 70.33% probability of exploitation in the next 30 days.

How do I fix CVE-2021-35393?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-35393?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST