CVE-2021-35393
CriticalRealtek Jungle SDK version v2.x up to v3.4.14B provides a 'WiFi Simple Config' server that implements both UPnP and SSDP protocols.
Published Aug 16, 2021 · Updated Aug 13, 2025
Key Facts
Patch immediately- CVE-2021-35393 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Rtl819x Jungle Software Development Kit (Realtek).
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 68% probability of exploitation in the next 30 days.
- Fixed versions are available, including Rtl819x Jungle Software Development Kit <=3.4.14b, Rtl819x Jungle Software Development Kit 3.4.14b.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
68%
Higher than 99.3% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
None known
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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.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Rtl819x Jungle Software Development KitRealtek | See advisory | 3.4.14b |
Patched Releases
Rtl819x Jungle Software Development Kit
<=3.4.14b
Timeline
Publicly disclosed
Aug 16, 2021
Last updated
Aug 13, 2025
Weakness Type
- CWE-787 Out-of-bounds Write
References
FAQ
Common Questions.
Realtek Jungle SDK version v2.x up to v3.4.14B provides a 'WiFi Simple Config' server that implements both UPnP and SSDP protocols.
Affected: Rtl819x Jungle Software Development Kit (Realtek). The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Rtl819x Jungle Software Development Kit <=3.4.14b, Rtl819x Jungle Software Development Kit 3.4.14b.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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